+4
I'm going to go with films that bring some sort of spiritual insight (... or something).
The Wizard of Oz (1939 - everything we need is already within each of us).
It's a Wonderful Life (1946 - the penultimate lesson about feeling bad for yourself).
The Elephant Man (1980 - when you're feeling bad, this movie makes you realize your problems are nothing, comparatively).
Revenge of the Nerds (1984 - a story about victory for those who are outcast and downtrodden).
Ferris Bueller's Day Off (1986 - it's hard to remain depressed upon watching this, plus, it can encourage you to relax and take a day off).
Planes, Trains and Automobiles (1987 - with a wink to Citizen Rules! Candy and Martin make some laughs in a story with some strong messages about loneliness, loss and friendship).
Heart & Souls (1993 - feel good movie with deep message).
Glory (1989 - Just a good movie that always takes me somewhere else).
Flatliners (1990 - why what we do in life is important, so make the best of it).
Shawshank Redemption (1994 - the "get busy livin' or get busy dyin'" thing usually helps motivate me).
Apollo 13 (1995 - a story of a real life miracle against all odds that's always uplifting & just a good movie to boot).
Castaway (2000 - survival movies help put things in perspective).
Too many to list, but just about any sports movie will do - almost all of them are good to help get you out of a funk - I think that's why they are one of my favorite genres even though I have little interest in real life professional sports.