I have a dell 4500S with xp pro on it. Today it won't boot all the way. It comes to the logon screen and after you enter the user name and password and click OK it goes to a blue screen. No start button, taskbar, icons or anything normal. All that comes up is the box from Microsoft saying that windows explorer has experienced a problem, do you want to send a report. If you click out of that box, it goes back to just being a plain blue screen. There are no error numbers for me to look up, just plain blue. When I hit F12 for boot options, there is no option for Safe Mode. Any suggestions