I'm starting to watch films that will hopefully become the subject of my dissertation.
Nuit en Brouillard or Night anf Fog (so called because of the mysterious trains that came in the night and fog to take Jews to concentration camps) is a short half and hour French Documentary about the a number of different subjects relating to the Holocaust. Obviously a film dealing with this subject is going to be very unpleasant, Night and Fog is pretty shocking even for what you would typically expect, doesn't shy away from revealing the details and very graphically and is generally regarded as one of the powerful films ever made.
I'm also in need of suggestions, I'm looking for War films that present war from untypical perspectives. For example Tora! Tora! Tora! shows the attack on Pearl Harbour from both the perspective of the American and Japanese forces. Whats interesting about Tora! Tora! Tora! is that the film is directed by both American and Japanese filmmakers so it lacks a certain bias. The Sorrow and the Pity is another interesting film to me as well as Shohei Imamura's Black Rain. Both films differ from typical conventions and message when it comes to showing events from World War 2.
Anyway here are the films on my list that I have watched or intend to watch.
Night and Fog (Nuit en Brouillard)
The Sorrow and the Pity
Tora! Tora! Tora!
Flags of our Fathers and Letters from Iwo Jima
Merry Christmas Mr Lawrence
Hell in the Pacific
The Big Red One
I need plenty more though. :)