So when you get the error (in your original post) are any file names
mentioned - either before or after you are prompted as to whether you want
to send an error report (assuming you get this prompt)?
I would suggest running Ad-Aware & Spybot anyway.
These have fixed many problems with IE, as you will see if you Google this
newsgroup.
I have no recollection of this being the case with a Symantec product. If
so, then kudos to them.
Also, I would run CWShredder at detect/remove some of the most nasty
malware:
CWShredder direct download:
http://aumha.org/downloads/cwshredder.zip
After you unzip (and launch the excutable file), simply click the FIX button
after checking for updates.
Finally, have you tried booting in Safe Mode, followed by booting in Normal
mode.
If you have you XP installation CD handy I would also run System File
Checker just to get a 'sanity check' on you IE files.
Go to Start > Run and type
sfc /scannow
Click OK
Good luck as this is a tough one without more information.