(I have not read the rest of the thread, so forgive me if there's any repeating)
Coming from a Jew with two grandparents that survived the Holocaust, I have done several reports on Hitler (mainly because I didn't want to do the standard Abraham Lincoln or Roosevelt or some tired out historical figure) and quite frankly I find him morbidly fascinating.
I recently came back from Berlin, very nice city I recommend it, and we visited a Labor Camp/Concentration Camp. Let me tell you, you don't understand how horrible the Holocaust was until you visit the site of it all. But anyway;
Hitler was a phenomenal speaker. If you've ever heard one of his speeches you'd know, he could captivate a whole audience with his speeches no matter the subject. He was able to get Germany out of the shit it was in after the Treaty of Versailles, and overall he helped the German people out of their own pity.
But he caused the Holocaust. He enstated the Gestapo headquarters, where the planning and preparing went in to create the Holocaust, how they'd build the Concentration Camps, how they'd execute them, how they would transport them, etc. Over 6 million Jews, or as I call them people, were killed along with 4-6 million (depending on the source) other "undesirables". In my mind, and I'm sure the majority of the world's, that is unforgivable, at least until history repeats itself...
Overall, we shouldn't look at Hitler as a supreme psychopath. Nor should we look at him as some "great leader" despite what he created. We have to look at him as a figure of history, respect his accomplishments, but acknowledge his failings and teach it to future generations. We should never forget what he did, but there's two sides to a coin, and if we don't understand why or how he came into power, or why and how he created the Holocaust, history will never learn and we will just go through it again and again and again.
That and he was attempted to be assassinated like, what, 15 times? Say what you will about him, that's a damn lucky bastard if I ever saw one...