I used to pay my sons to convert CD's onto a NAS.  I split the charge with them 50/50.  It was a nice way for a young kid to make a few extra $.  So if you've got a yougn kid lying around the house, I definitely recommend this route.  Personally, I'd never do it myself.  It takes a long time, based on the amount of CD's...

Then just install the NAS into the network and let him put the CD collection in the attic where it belongs.

Or you could show him how to use Napster or Spotify and be done with it.