"dbPowerAmp Batch converter." seconded! A classic.

RealPlayer is very powerful and clever, but it wants to control everything you do in music for the rest of eternity... *grin*....unless you refuse it permission thru a firewall, etc. I have a copy which I have tamed and clipped its claws for those VERY few times I want Real interface.

(As olddude says, there are other ways to convert stuff..)

I have this one specifically to convert Real Media to WAV or MP3