When I turn my computer on it will load up to the Windows XP start up screene but just as the computer loads the logon screen the screen will go black and will stay like this. Any ideas on how to fix this or why it is doing this. Thanks
Looks very much like a graphics driver problem. Reboot and press F8 to enable booting up on safe mode. Delete the graphics driver and again reboot. Hopefully you will be able to boot normally and then reinstall your graphics driver.