I've had this problem for awhile but I have never asked about it here. Every time i'm playing CoD4 online and the level Backlot comes up as the level to play next, when it's loading about 3/4 of the way through it'll stop and give me the "This Game Disc is Dirty or Damaged" messaged. I can load every other level fine but this one it never lets me, anybody know something I can do?

take it to the local game shop and ask them to repair the disc, only a couple of quid, same thing used to happen to me on crash, its just you're disc needs a clean.

Yeah, thats a fairly common thing in COD. You have some kind of scratch on the disk over some information used in that map, so the game has diffculty loading it. The only solution is to have the disc repaired or buy another one.

Ah!!!!! I totally forgot I made this thread haha, but thanks guys!

This is Totally normal, not to do with your xbox, most likely the part of the disc that holds the info about the maps has most likely been scratched/damaged, i have encountered this error alot, just take it to the shop you bought it from, if its a circular scratch (which is caused by the xbox, aka. a spindle scratch, google it), if its a normal scratch, im afraid your gonna have to buy a new disc/game sorry, hope i helped