My daughter has a Gateway 450 RGH laptop with Windows XP home edition on it; today when she went to log in it went straight to a black screen with a while blinking cursor in the upper left-hand corner. When I rebooted I did get the screen where you can do F10 or F2 and it would allow me to go to either; however, when I exit out, it goes back to the black screen and white blinking cursor in upper left-hand corner. Any assistance would be greatly appreciated.

Try booting from the XP install disk and running repair