IE 8 hangs up in Windows 7

When I click to open Internet Explorer 8 in Windows 7 Pro (64-bit), IE8 opens then hangs for 30-45 seconds ("not responding") before my homepage opens. Once the homepage is up, it acts fine unless I try to open a new tab. If I open a new tab, the 30-45 second hang repeats.

Here are the causes I've eliminated:

1. It isn't a virus or malware. A deep scan with Norton Antivirus 2010 came up clean. NAV 2010 loads at startup and runs Live Update constantly. A scan with Advanced Windows Care 3.0 showed no spyware issues.
2. It does not appear to be a HDD or memory issue. Chrome and Firefox start instantly with no problems, as do all other programs (Office, Windows Media Player, etc.).
3. Did reset on IE8. No luck.

If I try to close IE8 during the hang period, the "Windows is searching for a solution..." will pop up; however no followup box ("Unable to solve problem", etc.) follows.

Since IE8 is integrated into Windows 7, I cannot find a way to uninstall or repair it within windows. Microsoft's IE8 homepage will not let me reinstall it and I cannot find a solution searching Microsoft's online help.

System specs: Sony VGN-NW230G notebook, T6670 Core 2 Duo CPU, Windows 7 Pro 64-bit (Sony OEM version), 4GB DDR2 6400, Norton Antivirus 2010. No toolbars or crapware within IE8.

As much as I'd like to stop using IE8, I have one work program that prefers it over other browsers for accessing online help.

Any ideas on how to fix this would be appreciated. Thanks in advance for your help.

 

One more possible clue: The problem only occurs in my main Administrator-level user account. IE8 works fine in my secondary Administrator-level user account.