Thanks for the advices everyone.
I installed Audacity, and it's was just what I had been looking for.
As a side note: When you've removed the unwanted part of the song, you
have to save the song as a new mp3 file. In order to save it as a mp3
you need to have a dll file called lame_enc.dll, which can be
found at
www.dll-files.com (atleast that's where I got mine from).
/Svend Rost