knowing that Vista is crap
Not that I
entirely agree with you there, JAISP
but from today you can download the release candidate for Windows 7 from Microsoft and run it on a "free" license until June 2010. Worth a look, eh?
IE8 went on general release 19th March, 2009. It wasn't included in all Windows Updates, but rolled out in Vista updates.
Hmm.... weeuuurlll, that aside (!!), are you using an htaccess redirect for your
www.domain/domain issue? It might resolve the problem.