just picked up the Oblivion game yesterday ( older game ) because i heard it was good and only 30 bucks. anyway when i play it whenever i try to talk to anyone it usually (but not always) gives me the dirty disc error. eventually i examine the game to find out that my xbox has indeed scratched my disc ( which was in perfect condition prior playing it). I googled it and discovered that this problem was common.

Since i bought it recently ill be able to get a new copy of it , but the problem is that now my xbox is acting strange . When i tried to play COD4, which i had for about 8 months w/ 20 days play time with NO problems at all, it is giving me the unreadable disc error and when i examine the disc it has the same,distinct circular line on it as well.

Does anyone know anything about this? i read that first gen xbox's had trouble with Oblivion where as 2nd and 3rd gen models didnt. Also, when i did some research on it i discovered that there were 2 xbox trays, mine being the older and apparently defective version.

any tips?