@ karyoker
great minds think alike
ok well those are two different things.. you said your main problem was file size.. that happens as you SAVE the file.. not as you're recording and that's what I answered
ok.. well.. first you need to "rip" the song off the cd and put it to your hard drive.. then use the INSERT button on the multi-track view to put that backing into track 1..
then hit the "R" box beside track 2.. and start singing (check your record settings of your sound card mixer or windows mixer to have it set to record mic in or line in.. which ever you're plugged in as.. not "stereo mix" or "what you hear")
then press the Red circle on the bottom left corner to start recording..you should hear the track in line 1 playing.. and you sing and can see your wave in track 2
Clear as mud?? that's the start.. I'll see if I can find some of the sites I used to learn it for you ok??