Well WMP should be able to that on it's own.
On WMP10 I've got the D-pad set up as such.
Right - Next track
Hold Right - FastForward
Left- Previous track
Hold Left - Rewind
Up - Volume up
Down - Volume Down
Action(center) - Screen Toggle
That means I actually have to touch the screen to Play/Pause, but the set up has worked for me.
If you want a stand alone Screen program you could check out:
http://www.pdagold.com/software/detail.asp?s=1045
Best of luck!