Score-wise, you really can't get better than There Will Be Blood. The first discordant chord, at the very beginning - what a way to set the tone of the movie! The percussion during the buildup and the explosion of the oil derrick is worth the price of the movie alone. And the end, with Brahms - oh, how ironic. And the rest of the score was quite incredible as well. I do love 'Prospectors Arrive', that's a great song on its own and in the context of the movie is even better.
Other notable scores include Amelie - part of the quirkiness of the movie comes from the score, really, and the music is great as a standalone as well. I listen to it fairly often on my iPod and it's lovely. :heart: The Hours has a good score as well. Philip Glass - not surprising. Oh and The Assassination of Jesse James, too - I'd give specific examples but I can't quite remember it offhand!
Music: Garden State, hands down. Perfect, just absolutely perfect. 'Let Go', obviously, but also 'The Only Living Boy In New York' was quite perfect. Other movies... hmm. The beginning of Stranger than Fiction, with 'The Way We Get By' (Spoon) was nicely energetic. 'Everybody's Gotta Learn Sometimes' by Beck, in the beginning and ending of Eternal Sunshine - at the beginning it just provides the background to the grief Joel feels, but by the end it becomes quite strangely uplifting and perfect for the movie.
Oh! And Romeo + Juliet has really good songs too, very appropriate - the bass beginning in 'Talk Show Host', when they first introduce Romeo all pensive at the beach? The mysterious feel of the song really suits Romeo at that point in time. Desiree's 'Kissing You' is about the most romantic song and perfect for the lovers meeting, and 'Exit Music' was powerful at the end. Best ending-credits song, ever.