If you re-install (using an unattended installation for e.g.) XP recreates the accounts. As these accounts already existed, it has added it's own extensions to the Administrator part to make them unique.
Yes, provided you didn't save or don't want to save any of those settings. Although, you will get error messages if the are still active (e.g your most recent install may keep the Administrator.XPMACHINE.003 and bin off all the rest.)
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS