I'm especially fond of (in no particular order):
1. Amélie
2. The Hours
3. The Shawshank Redemption
Films which took me completely by surprise for sheer unexpected quality:
1. Donnie Darko
2. Leon
3. K-Pax
4. Sweet Sixteen
5. The Matrix (first one)
Other flicks that I'd always be happy to watch would include Miss Congeniality (I know, I know, but ol' Sandra Bullock just, well, y'know), Monster's Inc., Spy Game (espionage nonsense but enjoyable all the same), Lock, Stock & Two Smoking Barrels (for some of the superb lines in the script if nothing else), 8 Mile (rather prejudiced no doubt by my worryingly deep liking for Eminem), Dogma, and many others.