my mind secedes

I own the xbox version of kotor2, and I often experience freezing at the first Obsidian screen, the "press start" screen, and while loading. It has progressed to a level of severity that I have to try 5-10 times of restarting just to get a game to load. I bought the disc brand new when it came out and it irks me that I have had nothing but trouble with it since then. Does anyone have any advice?