Another impossible question! 'The Matrix' is good, but my favourites are 'The Usual Suspects', 'The Sixth Sense', 'Mononoke Hiri' and probably several more I can't think of right now.
'It's a Wonderful Life' is one of the ones that comes close... Recently, I enjoyed all the films on Waterwolf's list, but I'd add Crouching tiger. I know purists say that it's been done before, but it adds something that the Legend of Fong Sui Yuk didn't have. Also, fight Club has to get a mention...
My all-time favourite is Woody Allen's 'Annie Hall. mainly because I identify with the hero's success rate with women in his life! I also love 'The Blues Brothers', and I'm always cheered up by watching The Queen's favourite film, which is (stand by to be impressed ...) 'Yellow Submarine!
The Longest Day is class, and of course The Usual Suspects is hard to beat, The Matrix is super as well. Saving Private Ryan. The Mummy and The Mummy Returns, I could go on :) Happy New Year everyone