Documents and Settings contains much more than your data. If you want to
move your data to a second partition for convenience in backing up your
system, as I have done, just move the My Documents Folder.
You'll want to add some objects to My Documents, depending on what you
want to include in your backup. For instance, I moved My Favorites,
Outlook Express message store, and my Address Book to My Documents. I
also store preferences and settings for other software there as well,
such as my firewall settings and MS Office settings.
The rest of the Documents and Settings folder are items you'll want to
store in your system partition.
"How to Move Shell Folders (and contents)"
http://www.kellys-korner-xp.com/xp_shell_folders.htm
With the setup I have - and you will have - we can backup our system
partition (containing Windows, our programs and their configuration
files) separately from oour user files.
