We've talked about films and we've talked about hip-hop, but never really gotten into soundtracks. I don't know about BEST, but I can think of two tracks I've ALWAYS liked:
The Pharcyde - Pandemonium (from Street Fighter)... Sega and Pharcyde? That's a win-win situation right there:
I also love "Little Renee" by the Digable Planets from the Coneheads soundtrack, but I couldn't find a YouTube clip for it. Bummer.