Drm-Removal will remove DRM from your music. Convert protected audio and video.  

Easily convert DRM protected music files and various audio files to unprotected MP3, CD, iPod and other MP3 player file formats at high speed and CD quality - legally. With just a few mouse clicks you can enjoy all your protected songs on iPod, any other MP3 player, CD player, mobile phone or PC - without any restrictions or DRM protection.

Convert WMA to AAC

WMA to AAC Converter

WMA to AAC and various other formats converting software. Copy your music to unprotected files.

WMA format - Windows Media Audio (WMA) is brand name for compressed audio file formats developed by Microsoft. Currently, it is the second (after MP3) most widely supported format for compressed audio.
The music store service such as Napster uses WMA as their preferred audio format. Usually, audio in WMA format is protected.

AAC format is audio compression and encoding scheme for digital music. AAC is the default audio format of Apple's iPhone, iPod, iTunes, and the format used for all iTunes Store audio.

Convert WMA to AAC at up to 40x from original speed. Copy your AAC files and convert them to AAC format - native format for iPod and iTunes. To convert WMA to AAC, you should go to the settings dialog and choose AAC as encoder. Now all of your converted files will be in WMA format.
Take a look at "Compression Quality" setting. The highest value you choose - the more qualitive file you get and the bigger file as a result. Software can convert to AAC, WMA, M4A and AAC format. Converting is done in batch mode. You can listen for file being converted and any other converted or queued for conversion. If you want to compare quality, it's possible to listen to original and converted file, verifying, that conversion do not loose original quality.