"How can Ilog on as "Administrator" if so I don't remember any passwords"

You could use NTPASSWD to clear that Admin password.

But before I continue, how did you post such a terribly formatted discussion? Even your question does not have a question mark and a statement "now it went haywire" has the question mark. Something odd about this post.

Once you get the account reset you can deal with the dead accounts as if they have CORRUPT PROFILES. Microsoft tells you the steps at the next link. And about NTPASSWORD. It's free, found with google and I do not write instructions on its use since it's just a boot and answer one question then hit enter type software. Besides we have the web to look for that.

READ http://support.microsoft.com/kb/811151 on how Microsoft fixes that issue.
Bob