Vista IE issues

Try resetting IE...
Click start, type inetcpl.cpl, hit enter, navigate to the "Advanced" tab, press the "Reset..." button, check the option "Delete Personal Settings", click "Reset".

Alternatively, you could use this program.
http://support.microsoft.com/kb/9362...xItForMeAlways

If that does not solve your problem. You have a few options:
1) Try the steps mentioned in this article: http://support.microsoft.com/default...b/957700/en-us
2) Perform a System Restore

Lastly, if none of the above works Contact Microsoft or Reinstall Windows
No-charge support for Internet Explorer 8 installation, set-up and usage (only) is available via the phone based on your locale through 31 December 2009. Customers must be running Windows XP or Windows Vista in a non-domain environment. US & CA Residents: 866-234-6020.
Other: https://support.microsoft.com/oas/default.aspx?&prid=13043

IE8 Support page:
http://www.microsoft.com/windows/internet-explorer/support/call-us.aspx