Halo: Combat Evolved > All the other ones...
Reasons why:
1. Cortana was purple and a tomboy (Better color than blue, and I like the tomboy type)
2. Well designed, spent over ten years on it, instead of 4 (Halo 2) and 3 (Halo 3)
3. Delivery of the Flood was amazing in Halo 1, Halo 2 its like they didn't even try to capture the feel of the flood when they were first introduced, Halo 3 Flood introduction was cool, but not as good as a swamp, with no Elites, no Marines, odd things happening, a crazy marine muttering and sobbing, destroyed envirement, and then finally the Jenkins Headcamera scene!
4. Weapons were actually powerful, unlike Halo 3, in Halo 3 I felt like I was holding a toy, not a gun...
5. Mystery, you had to use your imagination, you got to figure out who the Forerunners were, and how everything came to be, in the manual it explained enough so that it kept you on track, but you could have fun.
6. The music was awesome, well all the soundtracks were awesome, but I like the them for "The Maw" best.
7. Incredible replayability, I keep playing Halo 1, I used to play halo 2 even more (Love the arbiter, and more flood levels) I only play halo 3 for custom games with my friends now
8. Bungie put their hearts and souls into it, Microsoft rushed Halo 2, and Halo 3...
Halo 1 = Masterpiece
Halo 2 = piece of beautiful art
Halo 3 = Diarhea (It was rushed out and fell apart quickly)
Halo Wars = Good RTS, but I am afraid that Ensemble Might not get it right
Halo 3 ODST = I dont know yet...
