<< EAC and LAME >>
Damn, way beat me to it.
I agree with him. These programs are easy to use, and they produce excellent sounding MP3s, IMO. Depending on how you want to do this little project though, you may want to use a third program called lame batch. It all depends on how much space and time you've got.
If you're low on HD space, and want to rip and encode one CD at a time, just set EAC up to use LAME as an external encoder. The program will then rip a track, open LAME & encode to MP3, then erase the WAV before moving on to the next track.
If you've got a lot of space on the other hand, try LAMEbatch. This time, just set EAC up to rip the CDs, and leave the external encoder off. Rip a few CDs onto your hard drive, then open LAMEbatch, select all the ripped tracks, and let the program crank on encoding the MP3s overnight or while you're at work/school. When it's done, just go back and erase the WAVs yourself.
Either way, LAME needs a frontend like EAC or LAMEbatch to get the most out of it. The program itself will only encode at 128kbps and joint stereo when you drag a WAV over it; the frontends allow you to tweak this for higher/lower or variable bit rates, mono or forced-stereo sound and some other things.
Hope this helps.
Nate