iTunes is probably the worst audio CD ripper there is. There's pretty much ZERO error correcting -- the option for error correcting is only for jitters.
Exact Audio Copy is the best ripper out there...unfortunately, it's Windows-only. The closest thing on the Mac that there is is Max, which does a good job. Stopped working on my MacBook after I upgraded to Lion, though, but interestingly it works fine on my iMac, which also has Lion...