Halo 3 Disc Not Working Properly?

[daniel]

Hi yesterday my friend game over with his xbox 360 elite, he had Halo 3. He said it wouldnt work but he spent 20 mins wiping it before he came, and it worked. We went on MW2 for a bit and decided 2 go back on halo, it said that it couldnt read it, after loads of time my mum spent wiping it it still came up with the same problem? any ideas?
it was knocked over, made a kluncing noise and now has a ring arround it sort of, Help!

 

[Discovery]

does the xbox play Other games ok my sons xbox started playing up like that it wold only play some games ok then after a day or so it stopped reading the games and ejecting them i sent it back to Microsoft and they fix it and Sent it back. but if the xbox is ok it must be the disc where i live there is a game shop that cleans discs in a machine for £1.50 and it gets all the scratches out and even the xbox scratch out