XP backup

I have never used it. I just installed XP on a new computer and have

it set up like I am used to it like switching the look back to

Classic.

If I do accessories/tools/backup and chose "my documents and settings"

can I assume that it saves all program information. I know it does

not save the actual program, but does it save settings I have made to

change the program defaults?

On my computer I have only one user and a guest.

What if I want to restore this backup on another XP machine? Can I

just install the backup and have my username added to the users on the

computer?

If a hard drive crashes and I reinstall XP, can I add the backup file

first thing. Do I create the same username on the new install and

then restore the backup? Can I have another username on the computer

and install this back up ot it's settings?

Thank you for your time