Here is my top 10 Xbox Games to speedrun in no particular order:

1. Psychonauts
2. Spider-Man 2
3. Prince Of Persia: Sands Of Time
4. Dead Or Alive: Ultimate
5. Star Wars: Knights Of The Old Republic
6. Beyond Good and Evil
7. The Chronicles of Riddick: Escape from Butcher Bay
8. Ninja Gaiden
9. Half-Life 2
10. Halo: Combat Evolved Bonus Halo 2

Have Fun and Good Luck