No one appears to have mentioned the Emergency Boot Disk - it's
very useful!
Control Panel / Add~Remove Programs / Startup Disk / Create Disk
It's probably worth mentioning again how useful it is to have several partitions on your hard drive (or several disks!). Keep all your documents including favourites and address book (requires registry tweek) on a separate partition, well away from windows. Also, keep a copy of the windows CD (and any other common ones) on another partition. Then, when it comes to reformatting your windows drive, you don't lose all your work and you don't need to worry about CD drivers - it's already there.