EVERYTHING...
I mean, everything that you can possibly need for music file format conversions is available from another SourceForge developed application...
It has been carefully hidden in my sig for about 2 years or so...
Click on
CDex 1.51 in my sig below...
There are also numerous posts on the few tips re: D/Ling and installing CDex 1.51 in various posts here in the Tips & Tricks Forum...
Have a search for CDex...
Only thing you need to take care with is to properly... I mean PROPERLY setup the configurations for WHERE and HOW you want the resultant files to be saved and how they will be 'named'...
And, what 'quality' you wish for your conversions, depending on what file type you desire...
The HELP files are very good...
See also,
http://www.monkeysaudio.com/
(Which is also deeply hidden in my sig !!!) LOL
It is not difficult and only needs some thinking and careful reading to understand exactly how to save your converted stuff the way you want it to be...