Backing up my OS: how?

I am wanting to install another OS on this computer that I'm on right now, and make it a dual-boot with WinXP and CollegeLinux(or the like). I was wondering if there is a way to back up every single piece of data that I already have on my hard drive in case something wrong happens during my installation and repartitioning of the other OS. Thanks. :)

You could use norton ghost that will back everything up it will write images to CD-R/RW DVD-RW DVD+RW DVD-r DVD+r and Iomega Zip and jazdrives

or You can try Drive-Image www.drive-image.com