Windows XP refuses to load. I turn the computer on, and it works completely fine until just after the welcome screen when the desktop should be loading up. Instead, I get a black screen with nothing but the cursor in the center. I can move it around just fine, but the desktop doesn't load. After about 10-15 seconds of idling it restarts itself and repeats what I just described above. So I tried hitting F8 at startup to load from the last known good configuration, and I get the same result. So I tried to go in under safe mode, still nothing. I have no idea what to do to fix the computer. Ideas and suggestions would be VERY much appreciated.
EDIT (after reading the "when posting a problem" thread): I am running Service Pack 1 under XP Home Edition, pre-installed on my HP pre-assembled computer. I do not have a Windows XP cd-rom, nor a startup floppy disk.