[Europa Europa][1]
A Jewish boy separated from his family in the early days of WWII poses as a German orphan and is taken into the heart of the Nazi world as a 'war hero' and eventually becomes a Hitler Youth.
This one is historical, funny, improbable (though apparently based on a true story) and most of the dialogue is fairly clear.
There's some Russian dialogue in there too. [1]: http://www.imdb.com/title/tt0099776/