Yeah, Mass Effect 2 is leaps and bounds better than the first one, but ME1 is more important since it starts the universe. Man, such amazing games.
Yeah, pretty much every planet you come in contact with is vibrant in the second game. Although, collecting resources from planets using probes is a major pain, one they need to do away with much as they did the Mako missions from the first.
I can't recommend Alan Wake. Beyond the atmosphere, it falls short. Combat is repetitive (and awkward) and so are the environments. Yeah yeah ME had many boring, gray worlds that you drive around in a car with shitty physics, but those were all side quests. If you stick to the main story and the side quests that don't involve boring, gray planets, you'll probably spend like 16 hours on it. Then you prolly will wanna play through it again with a different class. Well worth the $10 you spent on it. Still need to buy ME2 though...
I personally recommend getting COD:Black Ops-lots of fun to play with your friends NFS: Hot Pursuit-really great, like a new and improved burnout Madden 11-IF YOU like sports Mass effect 1&2- lots of fun... 2 was loads better, but you have to play through 1... it's the beggining. And i don't know, but am I the only person who didn't really like Fallout 3??? I don't know, it just didn't do it for me. Played 4 hours, but wasn't really engaging enough to pull me in... Don't know though... At the end, buy whatever game interests you most. And a microphone is necessary
If you have friends that play XBL, you need to get Black Ops and Halo Reach. If you can borrow the older single player games (like bioshock, oblivion, Mass Effect), don't buy them. Sure BFBC2 (though I haven't played it) is probably the better game than black ops, your friends will all probably own black ops and very few BFBC2. And people will be playing Reach for a good 3+ years. My 2 cents.
Doesn't occur to me as I own three consoles and two of them provide my online gaming for free. Y'hear that Microsoft? Won't even let me access Facebook you sly bastards.