First question: Are the scratches on the top of the CD (where the labeling is) or on the bottom of the CD (where the clear plastic is )?

If it's the top layer, you're scrod. Because that's the data layer, and if a scratch there has penetrated the silkscreen print ink and gotten into the actual data substrate, the bits are simply gone. I've had certain rippers like EAC be able to do enough retries and error correction on such discs to get a usable rip, but only if the scratch into the data layer was not severe.

If it's the bottom clear plastic, scratches down there are easy to buff out. When I worked at a jewelry store, I used to use the shop's buffing wheel to buff out the scratches, worked like a charm. These days, big record stores sometimes keep buffing wheels around just for the purpose of doing those kinds of fixes for their customers, so perhaps try some record stores.

You can also get manual hand-crank buffer tools at record stores. I've tried one of these, and it works but it's a real pain to use.