Whether you install one before the other, probably doesn't make much difference, but logic tells me that, if you are going to upgrade to Windows 7, then do that first before installing any more software.
The only reason you wouldn't do that is if you were going to wait for some time before installing Win 7, but wanted to use Office 2007 now.
Mark
I have a one year old HP desktop running Vista Home Premium, which was pre-installed on my desktop by HP..
I have since purchased DVDs of both Microsoft Office 2007 FULL version and Windows 7 UPGRADE version.
I have not yet installed either of them.
Is there a preferred (or logical) sequence for installing them??
Should I install Windows 7 UPGRADE first and then Microsoft Office??
Or should I install Microsoft Office first and then Windows 7??
Abd why?
Thank you.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic