http://forums.minidisc.org/downloads/index.php
Has a full download for offline installation of SS3.1.
You need to register on the forum before you can download it.
I tried it on a streamlined install of Win 2k. The main program loaded ok but some of the extra SS bits had some trouble with missing codecs (Windows codecs I think). Anyway for me on this install, SS itself worked OK, couldn't load up the simple burner though.
I have to admit that I'd messed about with Win 2K
A LOT and only played about with the SS install for a very short time (very early on a Saturday morning so not the best time

), so it may very well work perfectly for you.
In any case it's probably worth a shot given your present situation. Good Luck!
p.s. Please back up
everything before trying this!!