Coastie,
1. Old versions of Microsoft Office:
Myself and others have complained that older versions of Office don't install cleanly. The symptom is that starting up Word will always bring up the Office Installer and it looks for missing components. If you have already tried the install, and are having this problem, remove Office via Add/Remove programs, then before trying to reinstall (or install for the first time) make sure you FIRST turn of "User Access Control" (UAC), reboot, then install Office as regular. You can then turn on UAC.
2. Old Printers
If you have an old printer, especially one shared on a desktop that you wish to use network attached from the laptop through your home wireless network, that may not work. We had an old HP Deskjet 932c that though the drivers installed and all looked like it would work, when actually sending a job to the printer it never went through. The trick was to use Add/Remove programs, Add Components to add in the "Unix Print Support", then add the printer as a local printer, and instead of USB as the port, us LPR and then add the printer name, UNC.
3. Wireless Network and non-broadcasted SSID
I had to turn on the router's broadcast of SSID, temporarily, before I could add the new wireless network to Vista's list of w-networks. Then, once added, I turned the broadcasting back off. I have never had to do that before with XP.
TJR