Scratched CDs Need Help?

First, try exact audio copy in secure mode or plextools if you have a plextor drive, extract to .wav (lowering speed might help too, try different drives if possible). If there are uncorrectable errors reported (don't delete the .wav files in this case!), you might want to try some disc repair set. Some people use toothpaste or car polish with similar results. If the CD is very valuable for you, you could let some professional with special equimpent handle this step (-> Google "CD repair" "your city").

If the .wav files you've extracted onto your HDD still contain errors, no matter what you've tried, you can still use some declick/deglitch software to get rid of them. The result will be not bit-identical to the original, but still audibly perfect if the errors are not too bad. There's a free tool called deglitch that can do this automatically for a whole track, but the results are not always perfect, for manual correction, you can use e.g. Adobe Audition (free time-limited trial version available).