Go to Auto Zone and get this stuff by McGweyers (unsure of the spelling) plastic scratch remover. It is made to get scratches out of plastic windshields. You also need to pick up a microfiber application pad, so you don't scratch the disk up more.

Apply it as you would toothpaste and it works like a charm. I read somewhere that using toothpaste actually damages the disk more in the long run. Not sure how factual that is, but the above worked amazingly well for my Gears of War disk. It got to one point in campaign where it would freeze, but I haven't had the problem since.

Oh and again, it is Mc Gweyers (sp, guiers?) no clue... plastic scratch remover. If you go, you will know which one I'm talking about when the get to the section of windsheild care or something.

It's maguiers.... I think... fuck it, I think thats right.