Can I have ONE copy of Office, say, on multi-boot setup?

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Hi,
I need to reinstall winXPpro (groan), will be setting up partitions and boot management for other OS's, ***including Vista*** down the road.

Will I be able to set things up so that my copy-protected software --- heck, all my apps, ideally --- have only one instance on my system, or, at the very least, where I won't be seen by, say, MS as trying to run two copies of Office, even though it would be my purchased official copy running on just my own computer (same one I registered it on initially)?

I would appreciate any recommendations or thoughts on special details that would not ordinarily crop up under a routine install.

Many TIA,
SueB
.