Well I'm not sure where you get the idea that XP Home/Pro might be spyware. If you do submit anything to them for updates etc then it is not personally identifable and even it it was I think it would go against privacy laws for MS to use it. (but what do they care!)
Anyway. XP Pro requires online/telephone activation. You can get corporate keys which don't need activating but if you buy a copy in a shop then i'm 99.9% certain it will be internet activated.
XP is much like 2000. So there should be no network compatability issues. Although I find networks work best when all the PCs have the same OS for some reason.