My computer's gone crazy... (reboot loop)

...and we were getting along so well.

I have a Dimension 8200 running Windows XP Home.  Upon starting it this morning, I was informed that the subscription service on my virus protection program, Norton Systemworks 2002, was no longer installed.  The program prompted me to uninstall Norton Systemworks and reinstall.  I disconnected from the Internet and uninstalled the program.  Upon rebooting to reinstall Norton, I moved from the Windows XP loadup screen to a blue screen telling me that my system needed to be checked for... file consistency?  It began running step one of three (some sort of verification).  I was prompted to "push any button" to cancel the check, but all the lights on my keyboard went dark the moment the blue screen appeared, and the computer was not accepting keyboard input (my attempt to cancel the check).  After completing step one, the computer flashes a bunch of text on the blue screen, then a bunch of text on a darker blue screen, then reboots.  It looped like this for about five minutes before I was able to catch a glimpse of "F8" on the dark blue screen and tried pressing that.  I was able to tell the computer to start in safe mode, but I never got beyond the black screen with strings of white text running across it identifying the path of different files in the Windows folder.

Help?