I guess it depends on what you mean by 'easiest'.
Probably the technically simplest way is to use a Hi-Fi cassette deck connected by an audio lead to a standalone CD recorder. Easy to use, but not very versatile.
If your PC has a CD burner installed then you could take a lead from your stereo, or a seperate Hi-Fi cassette deck - there's loads cheap on e-bay - into the 'line in' on your PC's soundcard. Possibly the ultimate convenience would be to install a 'PlusDeck2' into the PC - this is a cassette deck which mounts in a drive bay ! ! !
Remember that cassettes are much lower quality than CDs so you'll benefit from the fact that the better the quality of cassette deck you play the tape on the better quality of sound you'll recover from it. In fact, if th CD player you are going to be playing the CDs in can decode MP3s then you might as well encode them to MP3 and get a couple of hundred songs per CD.
Hope this helps.