The amount of uncorrect facts found in this thread is simply amazing.
I've been spending the past two or three years reading as many books as I could about the USSR and Nazi Germany, and I am shocked. Not that I can blame anyone here, I'm 100% sure that I'd be posting wrong facts about any other subject since I don't know much.
For example, flying_phoenix, Hitler didn't want to conquer the whole world. At least, not until he lost his mind when it became clear that Germany would lose the war.
Based on the advice of Karl Haushofer, he tried to conquer a "lebensraum", that is to say enough territory to provide enough resources for Germany. Haushofer (well known geopolitics theorist) also said that Germany should keep from attacking the USSR and try to work things out with the British Empire in order to survive. Mind you, this all happened almost 20 years before WWII even began. And Hitler did not completely listen to him in the end. Later, even though Germany was trying as hard as it could to destroy England, they kept trying to sign a peace treaty with the British Empire, offering them to keep their colonies, and even promising to remove troops from Benelux and France. Hitler didn't really care about controlling the whole world directly, as long as he could expand Germany's territory eastwards.
Not quite right, Haushofer didn't give advice to Hitler on the idea of Lebensraum, it was Hess that helped Hitler develop these ideas in Mein Kampf. Haushofer and Hess' close friendship (from their relationship when Hess was a student of Hausofer at Munich University) led to Haushofer's visiting of Hitler and Hess in Landsberg and giving Hess Friedrich Ratel's 'Politshe Geographie' (as well as Clausewitzs On War) in which the idea of Lebensraum came from.
It was through Hess that Hausofers ideas and concepts were incorporated into Nazi Party strategy.