I have Windows XP loaded onto my computer.  My computer recently caught a
virus through Facebook.  I tried running one of ADG 7.5 to get rid of the
virus.  Every time I was prompted whether to repair an error, I clicked
"yes."  Now when I try to start my computer, XP starts to load, then the
screen goes black and restarts before it reaches the login page.  I am a
COMPLETE novice on dealing with OS --or any -- issues.  Do I just re-load XP?
If so, do I need to do anything to "scrub" the system?  I can't start in
safe mode, so I don't know how to access anything currently on the hard drive.

hopelessly clueless