If you're looking for a good game check out Oddworld: Stranger's Wrath. It's a FPS that lets you switch to third person at times to do some platform type jumping. Most of the game is FPS and it is soooo much better than Halo 2.
Just shooting the same 4 weapons over and over trying to kill the same 4 enemies gets old, quick... Stangers Wrath only gives you 1 weapon but its a bad ass double barreled crossbow. You get to load up different types of live ammo that you have to gather during the game. (think digging for worms before fishing) There are about 10 different types of ammo that serve different purposes. You're a bad ass bounty hunter in Oddworld with an old west setting at the begining. You have to vary your ammo to try to bag the baddies alive. More money for live bounties than dead bounties, and bagging the bosses alive is no easy task.
None of the bosses are extremely hard; but some are alot more difficult to bag alive. Some of the bosses in the middle are harder than the end. That's really the only disappointment I had was the last boss. It was extremely hard to get to him, but he was a piece of cake.
The graphics and cut scenes are some of the best on the Xbox without a doubt. The sound is rather good too. Some reviews complain about the voice acting but I really didn't mind as I felt Stranger's voice fit in with the theme of what an old west gunslinger would sound like.
If you've played any other Oddworld games and enjoyed them, you should definately check this one out. It's nothing like the others as far as gameplay but it was 1000 times more fun than Halo 2. Just think FPS with Oddworld characters...:D