I have a dilemma. I'm running Win2K and really it's about time I upgraded; the dilemma is that I really want to be fully legal and buy my OS, but I have 2 PCs and buying even one copy is a real stretch to my resources.

A few questions:
1)Lots of people sell OEM copies with some random piece of hardware. Is this actually legal or a myth used to sell licenses which aren't actually valid for the person buying them?

2)Older versions are happy to be installed on several PCs. Is this possible with XPSP2, or would Windows Update break now they use the "genuine windows" detector?

3)Is there some cheap way to get 2 licenses cheaper than buying two copies (upgrades would do and XP Home is sufficient)

4)Although we have older versions of Windows and are eligible for ugrade versions, I'd rather install and completely wipe the drives -can upgrade versions do this?