I think the easiest and best way to do this is try to find the “audio in” plug on your sound card. It’ll probably have a little picture of a microphone above it. You then want to get a double sided microphone or headphone chord and connect it to your boombox. You’ll want to go to some place like radio shack to find it if you don’t have it, it should be fairly cheap.
Once you have that, connect the chord to your headhphone jack on your boombox and your microphone plug on your computer (sound card). You’re basically turning your boombox into a microphone.
Depending on what operating system you have, you want to go to start, control panel, sounds and audio device properties. You’re basically trying to fool around with the settings so that the computer will play the microphone as the “out”, so it’ll record.
Open up your copy of “sound recorder”. It’s default location from the start menu is “all programs”, “accessories”, “entertainment”. Try to record a few seconds and play it back. Record every track as you want them as individual wav files saving them all in the same folder. Then use your favorite cd burning software to make the wav files playable on your favorite cd player!
Hope this helps. I know the mid part is a little fuzzy but it should be helpful.