So legal issues aside - would that work?
Yes it will work and install on another system, you will have to call and get a new set of install numbers from Microsoft support but currently they won't stop you from doing it. They may ask a couple of questions but you can BS them if you so desire.
Personally though I'd stay with what you have if it's working for you. If you buy a brand new PC it will come with Vista if you really want to check it out.
