I just purchased this unit recently.  I was disappointed to see that a lot of the memory was already full when I received it.  Looking on the system, I saw that there was a bunch of Rhapsody music on the system that I didn't want.  I couldn't figure out how to remove it, so I finally went into the Rhapsody system and chose Format.

After it was over, I saw that the system was still half full.  I tried going through all of the folders and they were empty...

 I appreciate any help you can provide.