Removing User – restoring to new in XP

I want to delete all user accounts and restore the primary account to a new name. The problem…if an account exists with that name in any form, the system creates an account with appended with the computer name. ex., User “Frank” will get “Frank.FrankAtHome”. I need to keep all apps to prevent having to re-install them, so backup is necessary.
Can I safely delete my user accounts and later restore them to a new name?