XP User account not appearing at sign in

I established 2 new user accounts recently on a new machine running XP Pro. I had not turned off the PC in a few days, so today I shut it down. As I was doing this, it warned me that other users (I have a total of 3 user accounts on this PC) were logged in, and if I shut the macjhine down, those users might lose their work. When the PC rebooted, the "Administrator" user was not available during the login process, and the administrator functions had been assigned to another user account.

I navigated as follows, and discovered that the Administrator user account still existed - Start, right click my computer, manage, local users and groups (on then left) then users on the right. Administrator is listed there. When I double click that, a window appears, but there is not an option to allow me to display this profile during login. Obviously, I also can't get the profile to appear when I toggle betweeen users using "start" and "logoff".

I also did a system restore function from a point in time earlier today when all 3 acocunts did appear....but that did not restore the "administrator" user account for me.

My concern is all of the documents, and the Outlook email account that is tied to that "administrator" user account.....I just went through a huge battle getting things pulled together from when my last PC got freid and I can;t go through that again!

Help!