Also, if you are dual booting Windows XP and Vista, then each time you go into XP it will wipe out restore points on Vista. That is one of the reasons I run XP as a virtual operating system on my Vista Ultimate pc using Microsoft's free Virtual Pc 2007:
http://www.microsoft.com/downloads/d...displaylang=en
If you are going to continue dual booting XP and Vista and want to avoid wiping out Vista Restore Points when you log into Vista, you should read this tutorial:
System Restore Points - Stop XP Dual Boot Delete