Can't install any antivirus.

I recently uninstalled Security Shield antivirus and tried to install Norton Internet Security.  During installation I got a BSoD "'Bad Pool Header."  Every time I restarted the computer I would get this error about 2 minutes after startup.  I had to start in safe mode, uninstall Norton, and use system restore to get things working again. I then tried to upgrade my Security Shield, and after installing it I lost my Lindsky’s wireless internet connection.  Except for doing weird things to get a page to open, Windows would not recognize the connection.  Obviously, a software problem.   

I then installed Regserve registery cleaner, and it fixed about 1200 errors, but instead of clearing things up, it actually caused more problems.  Now I had no internet connection and Security Shield wouldn't close properly. 

My XPS gen 4  with Windows XP is five years old, so I used Dell Restore to return the software to its original factory installed condition.  Beautiful!  Everything worked fine again, like new — until I tried to install Security Shield again.  Once again it messed up my internet connection, and I was kicked offline.  I was able to use system restore to resolve this. 

I tried to install Norton antivirus again—and again got the “Bad pool header” and was finally able to restore to earlier time. 

Does this sound like a bad hard drive sector?  Everything works great until I try to install antivirus, even after using Dell Restore.

 

XPS gen 4 

Pentium 4, 3.2 gig

2 gig Ram

143 gig hard drive

Windows XP

Sound Blaster Audigy 2ZS

 

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I just restarted and hit F12 and performed a hard drive diagnostic.  It passed.  I don't know how reliable that is, but I'm clueless now. 

 

Thanks for the replies, guys.  I"m hesitant to install anything else.   I'm sure there's a BIG problem that needs attention, but maybe I'll just end up trying another antivirus like AVG so at least I have something.