See also:
Best VGM 378 - http://www.youtube.com/watch?v=SjEwSzmSNVo
A collection of my favorite videogame music. Note that most of them are from games I played so I might miss some great ones from games I never played.
Dreamcast / Xbox
Shenmue II (2001)
The Morning Fog's Wave
Composers: Check Wikipedia, the list is way too long