Old movies depress me.
I have a reason. It's not usually the content of the movie (though The Grapes of Wrath had me thinking a lot) but more of the actors of the movie. Take for example Rebel Without a Cause. The three main actors (James Dean, Sal Mineo, Natalie Wood) all died at a young age. Dean died in a car crash at 24 in 1955, Mineo was stabbed at 37 in 1976, and Wood drowned at 43 in 1981.
My point is a movie made between the 1930's and the 1960's usually make me feel depressed, mainly because a majority of the cast is dead now. And you'll never see their talent ever again.