Great movies, but might I add
Comedy: It's a Mad, Mad, Mad, Mad World, Kiss Kiss Bang Bang, The Brave Little Toaster
Horror: The House of the Devil, Donnie Darko, Event Horizon
Action: Man on Fire, Black Hawk Down
Drama: Chariots of Fire, Pulp Fiction, Reservoir Dogs, Dog Day Afternoon, Bullitt, Vanishing Point, Apocalypse Now
Musicals: Newsies, The Producers (Both versions), Little Shop of Horrors, Across the Universe
So many more that I can't think of right now...