Wilhelm II was viewed by many of the German population as an ineffective and weak leader, one of the harbingers of the downfall of the German reich.

He lived his latter days in exile in the aftermath of World War I, and his reign was a major inciting factor in how the Nazi Party managed to seize control so effectively - Wilhelm was a major propaganda piece, and the Nazis promised a return from the downfall of what Wilhelm brought upon Germany, from a disastrous war to the Treaty of Versailles and the crippling of Germany's economy.

This was somewhat exacerbated in terms of propaganda by Wilhelm's deposition of Otto von Bismarck. The German people in the Weimar Republic idolized Bismarck and Germany's second reich during his reign. Bismarck eventually resigned over continual leadership disagreements with Wilhelm, which was viewed by many Germans in the Weimar Republic as the beginning death knell for Germany's proud stance and heritage. Thus, in the Nazis' promise for a return to Germany's greatness during the second reich under Bismarck, they effectively embraced the already omnipresent distaste for the events of the past few decades under Wilhelm II to seize control.

In regards to Hitler: Wilhelm was "proud" of him in the sense that he admired his accomplishments, particularly in the beginnings of World War II, and sought to use Hitler and the Nazis as a platform to return to power (or at least the restoration of a monarchy). Hitler, of course, did not feel the same, and Wilhelm's sparse attempts at communication with the ruling party failed.

Sources:

The Coming of the Third Reich, Richard J. Evans, Penguin Publishing

The Third Reich at War, Richard J. Evans, Penguin Publishing

The Last Kaiser: The Life of Wilhelm II, Giles MacDonogh, St. Martin's Griffin

Recommended sources on this:

The Last Kaiser

The Kaiser and His Times

The short version is, the Kaiser initially had high hopes for the renewed nationalism of the Nazi Party, hoping that it would bring about a return of the monarchy and the reestablishment of the Reich as he understood it.

As it became clear, however, that a large part of the Nazi ideology hinged around the myth of the False Defeat or the Stab In The Back Myth the Kaiser saw that hope slip away. The power players in the Nazi Party - and Hitler especially - had little but contempt for the men who'd given the orders and signed the surrender of WW1.

Wilhelm II took particular umbrage at the treatment of Jews and had, according to MacDonogh, had a bit of a falling out with one of his sons over Kristallnacht. The son in question voiced understanding if not support of the violence against the Jews, while Wilhelm's reaction to the pogrom was to write "For the first time, I am ashamed to be a German."

Wilhelm II was a fairly complex guy. Pretty much any attempt to distill him down into a few paragraphs is going to be misleading and inherently unfair because, well, he's human. And we humans are rather complex creatures.

A few other posters have provided some really good book recommendations. /u/Killfile's recommendation of The Last Kaiser in particular is one I think you'll like. It's a good read, but it certainly has one flaw: it's a door-stopper. Historians in general have moved away from the Desmond Seward model of super-condensed information and that has both positives (like simply providing way more information) and negatives (like being a lot harder for new people to get into). Fortunately, YouTube has stepped into the breach by providing us with lots of interesting ways to engage people in history without requiring a major dedication of time. And, yes, The Last Kaiser is going to take you awhile to read through, especially if English isn't your native language.

So for you, OP, I'm going to specifically recommend this video. It's 6 minutes long, it's by the Great War guys (they basically do a week-by-week update of WWI as it unfolded a century after a fact plus some odds and ends like the linked video), and they have a German partner that runs simultaneous to it. I have no idea what your native language is, of course, so that may not be helpful to you.

If you let me know what your native language is, I'd be happy to see if any of the books recommended so far have translations available in your language.

The Emperor and the ruling aristocrats/bourgeois were subject of huge criticism from liberals and the working class movement like in the Simplizissimus. Germany had at that time a 3 class voting law, which gave workers the lowest amount of votes. Additional were parts of Germany very independent. So deported the city of Hamburg a last time 1912 an unionist, because workers weren't citizens. The workers movement at that time had not forgotten the laws against Socialdemocrats, which were canceled 1892.The emperor and his system were criticized from very democratic orientated liberals and the workers movement.

When in 1916 the consequences of the war caused hunger and the military took over the government, the Socialdemocrats were divided into USPD and SPD. The SPD had already excluded members which were against the war in 1914. The opposition against the war went eventually into a revolution in 1918. The Emperor migrated to the Netherlands. The SPD made a deal with the military and was able to establish a new republic after the military killed hundreds of leftists. The new republic gave all citizens even the women equal voting rights. A dream of liberals emerged to be true and the emperor was just someone who couldn't change Germany into a modern nation.