As far as starting with a CD copy, these have already been ripped to WMA. I'm not starting over. If it was my own collection, I might. But this is for a client that wouldn't have noticed the difference if I had ripped them into the highest compression MP3 format.

I found DBPowerAmp. I had a bit of trouble at first, but then figured out that most of the codecs aren't built in and have to be installed separately. After that little detail was fixed, it just has to run for the next 17 hours.