... So you wanna keep everything, but you want it shorter? Just from the perspective of... well.... ObviousFish, that isn't gonna happen. Unless you turn the song into one sung by a pile of chipmunks. :p
If you want it shorter, you're gonna have to drop something. The question is then... what. :p
Get yourself a copy of Audacity (
http://audacity.sourceforge.net/) and play with it some.