get cabelas trophy bucks or the new oblivion/bioshock double pack.

l4d2 Pre order it

Castle Crashers - Best game on Xbox 360.

Don't bother with Halo 3, but you MUST get Lost Odyssey and Mass Effect, I see you have FF X, so you will obviously like LO

You should be able to transfer your Windows Live ID to your 360. Microsoft uses a universal Gamertag. Your hotmail account ties with your XBL Gamertag/Zune Pass/Games for Windows

If you have to import games I'd definitely play a lot of XBLA games to save money. I recommend Castle Crashers (the more people you play with the more fun it gets), Braid, Shadow Complex, Portal: Still Alive if you haven't played it elsewhere, Splosion Man, and Geometry Wars 2.

Both coming to PSN, so as a PS3 owner, will probably prefer them on that platform, but I would definitely reccomend Shadow Complex, the others I haven't played

I recommend:

Cars Mater-National Championship      
Cars     
Viva Pinata     
Madden NFL 10     
Viva Pinata Trouble in Paradise     
Viva Pinata Party Animals     
Droplitz     
Astropop     
Marble Blast Ultra     
Forza Motorsport 2

Banjo Kazooie: Nuts & Bolts is a great game no matter what the haters say. Also, Viva Pinata is a fun game, if you get one, make sure to get Trouble in Paradise as it has all the bells and whistles with it. I'll be picking that one up eventually as well.

Download the demo, I liked the idea, I just found the game unplayable and not very fun. In fact, you can get demos for most of these