Having peeked at all the questions in advance, I probably find this question one of the hardest to answer, mostly because I don’t really know what falls in the category “drama.” Anything that’s not predominantly action or comedy, I suppose. Also, I think a dramatic film should deal with weighty, meaty topics. I think The Royal Tanenbaums is too comedic to be a drama, but it does deal with substances that have gravitas. See what I mean? Is Fight Club a drama because it deals with multiple personality disorders and many other considerable subjects? Hard to answer that one.
There so many drama’s that I’ve enjoyed and I’m hard pressed to name a favourite; Festen, Hana-bi, Leaving Las Vegas, Bad Lieutenant, Dog Day Afternoon, Donnie Darko, Leon, The Pianist… I think I will have to go with The Fountain. Not because it’s the best, or because it’s got endless rewatchability, but because the last time I saw it I needed two days to recover from it.