|"i was trying to remove the logon window"|
We have no idea what you deleted. Did you try to re-activate? You may have to do a "repair installation" of XP. Doing so will wipe out all Windows Updates that have been installed & all of them will have to be reinstalled again. Before doing that, try using System Restore to roll back the system to a time before you started playing with the settings.
BTW, all you needed to do was use google to find out how to remove the logon screen & automatically log in. IMO, using TweakUI is the best method: