AaAaAA! - Good, but gets kinda tiring after a while. The in-your-face presentation was overwhelming for me, I really didn't get it.
Beat Hazard - Just another indie game that gets kinda popular for taking something from Audiosurf, which wasn't that good in the first place.
Delve Deeper - Don't know about this one, doesn't look too good.
Zombie Driver - Excellent. Really, I mean really, good. New huge updates bring a lot more life into what would've been a stale game.
Company of Heroes - Hands down the best RTS of all time. Get Tales of Valor as well, it gives you all of the extra multiplayer content (new factions, etc.)
GTA:SA - I'd go with GTA4 and spend a bit extra money.
KOTOR - I can't believe you haven't played this yet. Now that it's old, it's kinda lost it's lustre, and isn't as groundbreaking anymore with the likes of Mass Effect and Dragon Age. In other words, great at it's time, now, kinda meh.
Call of Duty WaW - If you're going to get any old CoD, get the first Modern Warfare, or grab the 2nd one while it's on sale. Don't get WaW, it's terrible.
Team Fortress 2 - Why not? No need to explain anything here, great game.
Bejeweled 3 - Really? I'd go with Puzzle Quest first (basically Diablo with Bejeweled as the combat system, really great game), and if not that, Peggle.
Monday Night Combat - Don't know about this one. Whatever.
Super Meat Boy - Get it, but if you're like me and don't play games for the challenge, you won't like it as much. Be prepared to spend hours redoing levels because of their enormous difficulty. Most people claim that's part of the fun, you can decide that for yourself.
Depths of Peril - What? Never heard of this.
All in all, you have a fairly good list of cheap games, with some glaring mistakes (please, whatever you do, don't get World at War) but otherwise you're fine.
