I am shortly to buy a new Vista PC and in preparation I have ordered a
retail upgrade copy of Office Professional 2007 (I have a retail Office
2000 Premium CD to base that on).

The new PC will have MS Works 8.5 preinstalled. How do I stop Office
2007 upgrading that OEM software?

I don't want to uninstall Works but I do want Office 2007 to upgrade
Office 2000 so I that I can maintain licence flexibility if I later move
the installation to a different machine (not least because as retail
customer I want Office 2007 on my laptop as well).

Thanks.