HELP! Whats going wrong??

Hi guys,
been looking for a good games site and found you. Will be staying here.
But I need a little help if you dont mind.

Had my Wii modded with Wiigator and Homebrew (still not sure what that is yet).
Got a free game with the mod, Cheggers Party (cheers mate) that plays a bit jumpy. Thought I could do better so downloaded Monopoly and Deal or No Deal (for the missus, right?).
Burnt them to disc - perfect! They play smooth every time.
But since then every other game I put to disc will not play. All I get once the Gator screen has come up is a blue screen and error code 002 - I think it might not be reading the disc?
If I try the first two they run with no problems.
Does anyone have any ideas before I go MAD!!!!
Cheers guys.