For anyone experiencing a problem with Internet Explorer crashing instantly after starting, and the issue began December 15th: Take a look in Start Menu -> Control Panel -> Add/Remove Programs and uninstall Yahoo Toolbar if you have it, then try Internet Explorer again.  
Possibly either Yahoo pushed an update that is causing a problem on some computers, or one of the Microsoft updates of 12/14 is conflicting with the Yahoo toolbar. 
If this does nto help, or you need additional support, please do not hesitate to reach me in the Technical Assistance Center (TAC).
Brice Stevens
Technical Support
(540) 443-3398