Running WSS 2.0, IE 7, Office 2003 AND Groove 2007 - recently IE 7 crashes everytime I try to open an Office document. PDF documents open just fine. The error was:
"Internet Explorer has encountered a problem and needs to close. We are sorry for the inconvenience."
Googled and tried several suggestions that did not correct the problem, including remove the Office Tools - Windows SharePoint Services Support (under the advanced add/remove for Office2003).
This worked from Microsoft MVP post - Outlook by the Sound (Paul Hollis) Guess it was due to having installed Groove 2007. Even after deleting the owssupp.dll - Groove 2007 continued to work
From: nick <nick discussions microsoft com>
Subject: RE: Office 2007 crashes IE7 with MOSS after updates
Date: Sun, 14 Jan 2007 13:00:01 -0800
Newsgroups: microsoft.public.sharepoint.general
The problem happens when you have, or had, two versions of office installed. You have to go into your program files directory and delete the version of owssupp.dll you're not using (for example if you upgraded to office 2007 and then downgraded back to office 2003 you delete owssupp.dll in the office12 directory). IE 7's manage addons you can see two versions of the owssupp dll registered so IE gets confused and you have to forcefully remove the version you're not using anymore.
Additional note:
Some additional information from Microsoft (KB 833714) can be found here.