Graphics: Half Life 2
Vehicles: Halo 2
Weapons: Half Life 2
Enemy AI: Half Life 2
Friendly AI: Halo 2
Maps: Half Life 2
Story: Half Life 2 (The whole HL story is cool)
Music: Halo 2
Sound: Half Life 2
Physics: Half Life 2
Characters: Half Life 2
Cooler Armor: Halo 2 (helmet = rock
"Drama" factor: Half Life 2
"Scare" Factor: Half Life 2 (Halo 2 isnt ment to be scary)
Gameplay: Half Life 2
Potential for a Movie: both
Overall: Half Life 2 blew away Halo 2 but thats PC vs Console...