I don’t really like any of the Lego games (Batman, Indiana Jones, Star Wars). They start off alright, but become boring quickly. I’d only recommend them if you want some easy achievement points, or need a game to entertain someone who doesn’t play games often (young children, the elderly). Also, the characters don’t talk…they just grunt or giggle or make stupid noises.

Ninja Gaiden 2 – It’s a fast-paced action game with a ridiculous level of violence (TONS of blood, severed limbs, decapitations). Which, considering the games you have (COD4, GTA4 & Soul Calibur 4) , shouldn’t bother you too much. If you liked God of War for PS2, you’ll LOVE this game.

Gears of War – It’s a shooter game similar to Halo, except it’s from a 3rd-person perspective (the camera is behind the character). Some people prefer it over Halo. Also, the sequel comes out in November, so you could probably find a good deal on this one somewhere.

NCAA Football 09 (or Madden 09) – Personally, I think NCAA is the better game, but you can’t really go wrong with Madden. I’d say get Madden if you play against other people a lot; get NCAA if you’re playing against the computer more often.

All of these games have demos available for download on Xbox Live…check them out…
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EDIT** Oh Yeah COD5 is coming out soon too!!!!!!!
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If you get any drivers games the wheels are really fun to use.

If you like to chat on it theres either a large keyboard (like a computer 1) or a small 1 which fits into where the headphones go
Bye
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Gamestation