We watched The Seventh Seal by Ingmar Bergman. Absolutely riddled with symbolism, and quite brilliant really.
http://imdb.com/title/tt0050976/
I also recommend Memento, Million Dollar Baby, Strangers on a Train. I think it might be cool to do Cruel Intentions. It's based on a book set in the 1700's, oddly enough. lol. Also perhaps Harvey, Arsenic and Old Lace, Bringing Up Baby...
Gah I'm so jealous. I'm thinking of all these topics to go with these movies...and now I want to take a film class :P