I've been using Vue6Infinite with Vista for over 12 months with no issues.
There are many things you need to do in Vista before running anything, most problems with Vista are down to peeps not preparing properly, no offence intended, Vista is a whole new beast to any Windows OS you've used before, until you tame it that is!

You've already said you're runing in admin mode, next is switch off the UAC, causes more problems that it's worth IMO, next check that all your folders have "full permissions" set, Vista sometimes has your top level folder on Full, while leaving the sub folders not on Full, it shouldn't do that but it does, unless they've fixed it with recent updates, I haven't checked.
Do those and see how it runs then.

Injustice will be avenged.
Cofiwch Dryweryn.