Welcome screen, but no Login Names

[Broaddus]

I need help to remedy a problem that has developed with Win XP Home Edition. One day, I turned on the PC and it loaded up the Welcome screen and login Screen, but there were no log-in names to select. I pressed Ctrl-Alt-Delete twice and a I get a log-in screen, but have never had to put in a password before, so I am at a lost. It won't just let me press enter and I can't get pass this point. F8, safe mode does the same thing (stops at the login screen and the rest), so does trying to boot to a command prompt. Nothing happens differently when I select "Use the last good configuration. Basically I am stuck. I see people with simular problems on the internet, but no one has come up with a solution. Microsoft has a solution that remedies a problem somewhat like this, but it requires that you access the registry, which if I could do I would. I can't get that far. I am stuck at the screen with no log-ins and the log-in screen with no password. I even tried using administrator. Nothing! Any advice is greatly appreciated.