Being "content" is a difficult concept, and not an absolute one. There is always something left to want -- more territory or resources to take if they were available for free. It's probable that no one is ever content in the sense that they have nothing left to want.

What matters in practice is whether or not a state is willing to pay the costs involved in taking more. But those costs aren't fixed, they depend on how others will respond/resist. Many goals are worth pursuing if the cost is diplomatic disapproval but not if it is total war. Germany and Japan weren't content or satisfied in the first sense (and probably no one ever is) but whether or not they could be content in the second sense depended on the behavior of their adversaries. It doesn't matter if Japan was satisfied with the territory it had at some point if the United States was sufficiently dissatisfied with that division to fight or keep fighting.

This is an area of international relations scholarship known as bargaining theory, and the basic conclusion of bargaining theory is that it should always be possible to find some way of dividing international goods so that both sides are satisfied (in the sense that they won't fight to change the division, not in the sense that they have everything they could possibly want). This is a necessary logical conclusion of the fact that war is costly -- because the act of fighting consumes resources, it should always be possible to find a peaceful division that is better for both sides than what they could get by fighting. This hold in the abstract, but there may be practical obstacles that prevent reaching such a settlement.

That's all international relations, not history, but to get more concrete, let's imagine that Konoe or Tojo or whoever had a crystal ball and could foresee the way everything would end up through the atomic bombings and Japan's defeat. Clearly, accepting Japan's border as of 1931 -- much less 1940 -- would have been better than war with the United States. A Japanese leader with perfect foresight would have been content to take as much as possible short of provoking the war with the United States (maybe less than that depending on how you think a counterfactual war with China in the absence of the broader conflict would have turned out).

So, why weren't the Japanese content at that point? Certainly, part of the problem is that they lacked perfect foresight. You might imagine further imagine that they thought they could win a war with the US. In a truly fantastic article, "The Origins of the Pacific War," Scott Sagan argues that Japan (while obviously not having perfect foresight) knew they would likely lose the war yet attacked Pearl Harbor anyway.

But why? Sagan's argument is that the Japanese position in 1941 vis-a-vis the United States was only going to get worse. As you probably know, the prelude to war was the U.S. imposition of an embargo on oil exports to Japan. Japan was almost totally dependent on U.S. petroleum imports, and once these were cut off, their position was desperate. No oil means that you can't operate your ships or planes or tanks or anything. This would leave Japan totally vulnerable to future American pressure/coercion and the United States would only get stronger over time. The Japanese concluded:

Even if we should make concessions to the United States by giving up part of our national policy for the sake of a temporary peace, the United States, its military position strengthened, is sure to demand more and more concessions on our part; and ultimately our empire will lie prostrate at the feet of the United States.

Japanese leaders likely could and would have been satisfied with what they had as of mid-1941. The problem was that the Americans were not satisfied (wanting Japan, among others things, to withdraw from China). Admiral Nagano summarized the strategic problem:

Japan was like a patient suffering from a serious illness. He said the patient's case was so critical that the question of whether or not to operate had to be determined without delay. Should he be let alone without an operation, there was danger of a gradual decline. An operation, while it might be extremely dangerous, would still offer some hope of saving his life.

The attack on Pearl Harbor, then, was an act of desperation resulting not from Japanese dissatisfaction with the status quo but the Japanese belief that the United States was dissatisfied with the status quo and would gradually undermine what Japan already had. The two sides couldn't reach a mutually agreeable settlement because of the shifting power relationship -- with the U.S. getting stronger over time, Japan could expect a series of escalating demands, and it was better to try the desperate stroke of fighting up front rather than allowing the Japanese position to wither away over time.

Historical "what ifs" are notoriously difficult to conclude since they become quite subjective quite quickly based on our understanding of key players' tendencies in an artificial set of circumstances. That being said, the likelihood of a prolonged peace based on German domination of Central/Western Europe and Japanese domination of Eastern/Southeastern Asia as a basis of said peace was unlikely in the extreme.

The Autumn of 1940 was without doubt the height of Axis domination in retrospect. Germany was in an active war with only Great Britain (and the Commonwealth), while Japan was in an active war with only China while in the process of expanding influence and control into Indochina at the expense of French colonial power (and maintaining an active belligerence with the Soviet Union without an official war). Germany officially sought a settlement with the Western Powers following the spectacular defeat of France and isolation of Great Britain, while Japan was still prosecuting a very much open-ended war with China, but had strategic flexibility without rival in the world at the time (Japan could choose to expand the Asian mainland war, attack the Soviet Union, expand into the Pacific, or consolidate their gains and come to an agreement with China). In the event, Great Britain did not have a serious political or popular movement towards peace with Germany in late 1940 (Lord Halifax' insistence on hearing Italian offers of mediation never really got off the ground, and Churchill was able to adroitly outmaneuver him when Halifax tried to force the issue), and following the conclusion of the Battle of Britain in Britain's favor their resolve was nothing if not stiffened.

Let's say for the sake of argument that there was enough political or popular will to force Churchill's government either to resign, or to entertain peace talks with the Axis during the height of the Battle of Britain. Britain accedes to Italian demands for an African settlement that cedes much of East Africa to Italy, and perhaps joint control of the Suez Canal as well as the demilitarization of the Mediterranean (Malta, Gibraltar, Alexandria, etc.). Germany demands recognition of the new Status Quo on the Continent, as well as some strategic naval bases in the Atlantic/N. America (perhaps Nova Scotia or the Falklands, or recognition of the incorporation of Iceland and/or Greenland into the Reich, or some combination thereof), and Britain, in turn, gets certain trade guarantees with the new German Sphere of Influence, and - crucially - extracts a German promise to repatriate all French POWs to Metropolitan France before the end of 1940 in a bid to revive the Entente at a future date.

OK, the "Treaty of Copenhagen" is signed and we have peace right before Winter 1940. What next? Great Britain and Germany immediately fall into a Cold War arms race for a strategic edge, and Germany turns towards its great ideological foe: the Soviet Union. Japan pressures Britain into ceding Asian colonies with limited success, and retains its strategic flexibility. In early 1941 Germany almost certainly still attacks the Soviet Union (earlier than what happened in reality as the Yugoslav/Greek crises don't happen without Britain as a viable Ally to either country), and Britain almost certainly uses this pretext to renew hostilities in 1941. Perhaps Germany is able to capture Moscow due to the earlier start date of Barbarossa, and perhaps that is sufficient to force a settlement with the Soviet Union (I find both scenarios unlikely in the extreme: even if Germany could surround Moscow in very late fall '41, they are still sucked into urban warfare at the end of a shaky logistical tether in fighting they are not tactically suited for and have the same problems they would encounter in winter '42-'43 at Stalingrad in reality). Perhaps Japan still attacks the US in the Pacific, perhaps not. Eventually the Arsenal of Democracy almost certainly enters the conflict under some pretext or other. The Grand Alliance still defeats the Axis powers due to overwhelming economic might, and as Nazi Germany is constitutionally and ideologically incapable of prolonged peace based on everything we know about the country and its leadership.

While this is a specific historical scenario, I think it is the most plausible "peace" scenario that could have occurred. The chances that Germany don't attack Soviet Russia are basically nil due to implacable ideological forces. The chances that Japan cease their Asian/Pacific expansion are also basically nil as the Japanese military has repeatedly shown their ability and willingness to successfully interfere with the civilian political process throughout the 30's and 40's. Eventually - given these political and ideological realities - the three most powerful states most reliant on the maintenance of the status quo ante bellum in the short term (i.e. the UK, the United States, and the USSR) would band together to defeat the Axis' New World Order. The only exception would be Germany's ability to outright defeat the Soviet Union - in which Germany was economically and demographically at a massive disadvantage for a long conflict even if they could isolate the USSR and fight them alone without American or British interference. Failing that scenario, the outcome is broadly similar even with a brief interlude of peace in Winter and Spring 1940-41.

There is no point at which Hitler would have been content to live in peace in Europe. The base motivating ideology of Nazism required the conquest and subjugation of neighboring peoples in a continuous test of strength that would both hone and demonstrate the assumed inherent superiority of the Germanic race. His vision for Europe was not only revanchist or colonial, but wholly apocalyptic. Continuous war was a necessary component thereof.

Timothy Snyder ably summarized Hitler's view as the belief that "ecology was scarcity and existence meant a struggle for land." He saw only the binary of conflict: races could either triumph by dominating new frontiers or else wither and be extinguished.

His vision was naturally one replete with hypocrisy, but in its essence there was no room for anything more than the most contingent, utilitarian cooperation or cohabitation with other peoples. He dismissed the prospect of integration: "[we] will never see subjugated, so-called Germanized Czechs or Poles as a strengthening of the nation or of the people; rather this represents a racial weakening of our people."

As it happened, psychotic pronouncements like that rarely mapped to reality as the German military encountered practical difficulties in its attempted conquest of Europe and the world. However, it reveals the core of an ideology that could not accept any genuine or lasting peace.

To the Nazis, the liberal ideas that defined the modern world: "political reciprocity" and any other concepts that "allowed the world to be seen less as an ecological trap and more as a human order," were dangerous in themselves because they were assumed to be the product of Jewish plots to erode natural racial division. That paranoia left absolutely no basis for rapprochement or mutual trust, upon which peace depends.

There's a revelatory anecdote of Gerhard Fricke, an academic and member of the Nazi Party at the time. In a sublime expression of Nazism's ideological emptiness, he could only define it in the negative: celebrating Germany meant standing against "democracy, liberalism, individualists and humanism, capitalism and communism." This is the very heart of the pathetic paranoia that animated Nazism. Always against, forever and ever, with a new enemy beyond every horizon.

Their belief, again summarized by Timothy Snyder, was that "the very attempt to set a universal ideal and strain towards it" was sure evidence of Jewish corruption. In their world "ethics as such was the error, the only morality was fidelity to race."

Nazism and Fascism cannot be bargained with. Given power, they'll get, or get got.

It's important to remember as well that the supporters are among those who get got. How many young Germans believed the promise of a better future and were delivered 120 cubic feet of Russian mud instead? These ideologies are treacherous by nature. Hitler was not ever going to deliver the peace and prosperity that he sometimes promised. His loyal supporters got none in return.

When there is only the struggle you are only ever a tool to be used and discarded.

It took so many lives and so much pain to learn this lesson the first time around, but I do fear we will have to keep learning it regardless.

I highly recommend Black Earth by Timothy Snyder, Hitler's Crusade by Lorna Waddington, and War and Genocide: A Concise History of the Holocaust by Doris Bergen as accessible introductions to Nazism's absolute betrayal of humanity.