Here's another quick Vista tip that might also save you money!  Although Vista comes with inbuilt firewall,  anti-spyware and parental controls, there's still no out-of-the-box antivirus (presumably much to the relief of the countless AV product manufacturers around the globe). So after a fresh install you'll probably find the Windows Security Centre looking something like this:

Furthermore, you might well find that the copy of Norton AV you bought in 1996 is not compatible with Vista, and probably no longer eligible for definition updates!

Don't let this scare you into rushing out to PC World and spending fifty quid on whatever Symantec or McAfee are pushing, unless you're sure it's what you want and need. There are free alternatives out there which will probably suffice for the average home user.

I'm currently using AVG from Grisoft which is Vista-compatible, has downloadable updates and is absolutely free.