I do feel the OP's pain though...I'v been yearning to do a re-edit of Superman II in amongst the many other edits that are released and despite all these having Dolby Digital 5.1, I'v asked before on how this is done and how you can remove dialogue/music but have never found out.
But Jaiman, you are a star mate. That is an absolute cracking read and now it gives me the impetus and more importantly, a little bit of knowledge of the right path to try and do this.