Corrupted Group Policy Object - Failure to Open Even after Reinstall

About 7 days ago, I was inspecting my Group Policy Editor
reviewing the different functions & snap-ins I could
modify. I was logged in as Diane, but I have fulll
Administrative rights, since this is a stand alone
computer running WinXP Pro. As I clicked a plus symbol to
expand it, low and behold my computer immediatelt dumps me
out to Dos & starts to boot up again. Needless to say I
can no longer get Group Policy Editor to open up, which is
alittle disconcerning since somehow my Internet Explorer
connection settings were hard wired & changed to Proxy.

I even did a reinstall of XP Pro to no avail, still does
not work. Any suggestions concerning troubleshooting GP
Editor and why my AMD Athlon XP 1800 has developed the
habit of exiting to Dos & rebooting at least once every
other day running WinXP? Maybe it is the software? Oh
what a surprise that would be,lol!

Any suggestions or help would be greatly appreciated.
Thank you