I'll take a swing at this, but I'll be frank in saying the rest of the question isn't really possible to answer definitively, anyways:

In things like Band of Brothers and Fury it seems like when a tank gets hit, that's it, everyone's done for.

Catastrophic kills, to use the official terminology for what you're describing, are a lot more rare than movies like this lead you to believe. Especially in WWII, when most forms of armor piercing equipment were solid; they would either penetrate, or not, and asides from shrapnel and spalling, or a direct hit to a crew member, it wouldn't necessarily cause the immediate death of anyone in the vehicle. For example, a tank could be hit in the turret by an AP round, and be a through-and-through. The resulting shrapnel may grievously wound or outright kill the entirety of the turret crew (2-3 men in most cases, depending on model), but the Driver and Asst. Driver could potentially bail out unscathed, even if a fire resulted. Many tanks had under-side escape hatches to minimize exposure to small arms fire for just such an emergency.

An AP round passing through your tank, could do any number of things to effectively knock the tank out of battle: Damage the engine, ruin the turret traverse, destroy the optics, the weapon controls, cause a fire (which would, in theory, eventually cause a catastrophic kill if not contained), damage the track, the axles, kill a crewman as mentioned, etc.

Finally, enemy gunnery, be it in the form of a tank, anti-tank gun, or tank hunters, were far from the only threat to your life as a crewman. Asides from unhappy accidents, such as a tank sinking into the ground and crushing you while you slept under it (Not uncommon in the Eastern Front during the muddy season), you would be quite exposed, especially as a commander. Life was far from healthy as well, and if it were not for the fact that you could 'stretch your legs' while in Laager or 'at harbour', I would compare the life of a tanker to that of a submariner. I quote:

For the tank crews, even in battle, there were hours sitting motionless, closed down beneath their hatches, firing an occasional shell merely to provide a receptacle into which to urinate. Inside their hulls, they were vulnerable only to direct hits from artillery or mortar fire, but they were often more ignorant than the infantry of what was taking place around them.

Hastings goes on to say...

The tankmen pitied the infantry, their bodies naked to every form of high explosive, just as most foot soldiers preferred the comfort of their trenches to facing the enemy in a vast, noisy steel box which seemed to [catch aflame] when hit...many of the best tank commanders were killed by small arms, standing up in their turrets for a wider view of the battlefield. Their greatest fear was of breakdown or throwing a track under fire, which would compel them to dismount. Corporal Bill Preston of the US 743rd [Tank] Battalion had been in action for 32 days when his crew came upon another Sherman bogged down in a hedgerow ditch. He was peering out of the turret watching his commander and wireless operator hitch a cable to the casualty when two German mortar rounds dropped in their midst. Of the two men on the ground, one was killed and the other wounded. Preston himself fell to the bottom of the turret paralyzed..."

(Pages 207-208, Hastings, Max, Overlord: D-Day and the Battle for Normandy)

Hastings is fairly accurate in his description of life for a tank crewman, on and off the battlefield. This may help form an image in your mind. Tank crews were subject to attrition like any other combat arm, and its more than a bit of an exaggeration to claim that every tank hit immediately became a geyser of fire. Other campaign histories, such as those by Nipe and Carafano, go out of their way to stress just how many tanks were returned to combat within days or near-immediately after a firefight; stressing that tanks were rarely killed catastrophically. Naturally, though, as I've pointed out, its not cut-and-dry. A tank may be returned to combat after its turret traverse has been fixed, but the spalling caused by that hit may have made the gunner of said tank a casualty. Often as well, being hit in a tank would result in hatches being jammed, and it wasn't the round itself that would cause the crew to become casualties, but rather their inability to escape the tank as fire spread. A final note, I want to stress that fires could cause catastrophic explosions, but not always. We have accounts of knocked out tanks burning for days with only minor secondaries of ammunition. Tanks in those situations are almost always irrecoverable.