Crash Course PC Game Boxes

My wife’s 11 year old Taiwanese nephew will start living us after this school year. I worked my way through all of the now outdated game boxes with my own kids. I started with Pong, Atari Space Invaders and Play Stations, etc. Now I need to make the nephew’s room a fun and exciting place for him. I think a good game box and some age appropriate games would be a good start. I DO NOT have a clue what to buy. Can anyone tell me what’s popular now and some good games. I see him playing some games with his cousins and they are the typical shootem up bang bang variety with ability to upgrade weapons with points. I know I wont alter an 11 year olds desire for violent games so I wont try but I dont want to go too far. Just a good box that wont be outdated next month and a few reasonably violent games (I dont think I can hope for less) all at a reasonable price. I keep hearing about X-Box 360 but, again I have no idea. Anybody have some good suggestions with breaking my bank account.