Anyone know of a workaround for getting Avid Xpress Pro to run on Windows Vista? Doubtful...but I'm hoping.

I don't use the program personally. I've never heard of it untill now, but it looks like an interesting program. A quick search around finds that if you give the program shortcut Admin Privledges, and run it in "Windows XP SP2 Compatability" mode... it should run the program fine. Sadly though, realtime video preview doesn't work... and you have to export the vid in order to see. Seems kinda like a waste of time... but hey, go for it.
Vista seems to f*ck everything up doesn't it?

EDIT: I was just searching over the AVID website and found that you can upgrade to Avid Media Composer (which is the new Avid Xpress, apparently) for about $400USD. Seems a little pricey, but if you've got the money, it may help your compatability woes.

Avid is a top editing system.

Unfortunately very pricey and hard to master.

I do not use it, so I am unable to help.

short answer... stay away from Vista.
Look at Avid's upgrade deals/shenanigans to MC4. For $10k, they'll upgrade your hardware along with the software.