Chris,
You can re-download the WMP default skin
here at the MS Windows Media site :D
That'll fix your problem - or should. Follow the instructions (
here) to install the skin, then soft reset the device! Make sure that you place "default.skn" in your "\Program Files\Windows Media Player" folder, though - even though it says to move the entire folder over, make sure that it is also in the root Windows Media Player folder.
HTH,
Nick