I think Young will be a backup somewhere, but he definitely won't be a starter. I think the same will be said of Alex Smith. Get a fresh start, get some time to develop and maybe be able to be a starter again.
For Minnesota, I think the smart thing to do would be to bring in McNabb for two or three years, keep Webb as #2 and draft a guy to be developed as a #3. The team is going to be resigned to mediocrity for the next couple years anyway, since there are a TON of vets who won't be able to be re-signed, so you might as well re-build it the right way.
That said, I would LOVE VY to go to Minny. The guy has NO work ethic and just isn't that good. What more could you ask for from the QB of one of your division rivals?