I wouldn't be too quick to do this either.
I've done it just once, myself, on a machine which simply failed to boot for
no reason that was clear. I can't recall the precise set of steps I went
through, but at one point I was offered a repair, and accepted the offer.
What followed was a Vist a install process which is pretty lengthy--an hour
or more, and opaque--very little indication of what is happening.
However, at the end of it all, everything was perfect--apparently exactly as
it had been before whatever event initiated the problem occurred.
See if you can wait maybe until tomorrow morning? That would give me a
chance to research the error a bit more --sometimes there's an unofficial
fix that work. And, I'd like to find an article describing the reinstall
process for Vista. For XP, there were some gotchas--and I'd like to be sure
the same is not true for Vista.