Your the second person that has said today that all their MP3s have turned into exe files...Maybe there's a new virus around
I'd recommend running an AV scan and see what that comes up with...
Also do a Hijack this log and have a look at the self examination site and see if you can see any nasties in it...
Also download AVG antispyware (formaly Ewido) and run that...
OK for all these links...
These guys will be able to help you with a Hijack this log and you can download it here...
http://www.bleepingcomputer.com/foru...howtutorial=42
To examine your own log....
http://www.castlecops.com/HijackThis.html
AVG anti spyware....
http://www.ewido.net/en/