Xbox doesn't read undamaged and clean Black Ops but reads other games?

Well if there is a crack on the disc no matter how big/small it is, thats obviously the problem, but if u dont think it is then it may be a "game glitch" this are some rare glitches that freezes the game at a certain point. Now if u think it is a "game glitch" then you should call 1-800-4MY-XBOX for further assistance