God of War 3 is awesome, you can get the 3 disc set with the first 2 games remastered for PS3 as well. MAG if you like shooters although it doesn't seem as popular as it was at first, not as many players on line these days. It is pretty cool but prepare to get killed out of the blue a lot.
There are free games available for download as well, check out Fat Princess. Pretty much a capture the flag style game but the flag is a princess that gets fatter when you feed her cake so she is harder for the other team to carry back to their base.
You can find a lot of good videos on fixing an XBOX with the Red Ring issue on Youtube
http://www.youtube.com/watch?v=hjjinHmEoss
http://www.youtube.com/watch?v=wsz0lNJ6JrQ