Hi,
From Control Panel> Internet Options> Advanced> uncheck "Enable third party
browser extensions." If that allows IE to work, another program is causing
the problem- possibly an adware, spyware type program.
Note: you should re-enable browser extensions after resolving the situation.
Work through the solutions (CWShredder, Ad-aware, Spybot) at
http://mvps.org/winhelp2002/unwanted.htm Also note the security tips on that
page.
Additional information at:
The Parasite Fight
http://www.aumha.org/a/quickfix.htm
More security tips at
http://www.aumha.org/a/parasite.htm
Bugs, Glitches & Stuffups:
http://www.mvps.org/inetexplorer/Darnit.htm
If not caused by malware, consider disabling (for diagnostic purposes)
legitimate programs running in the background which might be interacting
with IE- security, antivirus, firewall, ad-blockers, toolbars & other
add-ons, etc.
You may have to uninstall then reinstall, or not reinstall, a program. Some
programs need an update to work properly with XP SP2.
Hope this helps,
Don