You need some audio editing software... Cool Edit (now bought by Adobe), for
ex. You might find some free ones for download on the web - ex. Audacity.
1st, you have to copy the audio files on yur hard drive in a format that
your software can open (.cda to .wav or .wma for most Audio CDs).
Alternatively, you can record straight from the sound card.
2nd, process/edit the files anyway you want, then save in a format of your
choice - depending if you need compression etc.
Hope this helps,
Michael