Hi,
Try these 1st - clean-up if possible and then rerun the Windows Installer.
Utility Spotlight Windows Installer CleanUp Utility
http://technet.microsoft.com/en-us/magazine/2008.08.utilityspotlight.aspx
Description of the Windows Installer CleanUp Utility
http://support.microsoft.com/kb/290301
Windows Installer 4.5 Redistributable
Run these to see if they can clear up the update installs.
Description of the Patch Registration Cleanup Tool
http://support.microsoft.com/kb/976220/
How do I reset Windows Update components? - a Mr Fixit
http://support.microsoft.com/kb/971058
Description of the System Update Readiness Tool for Windows Vista, for Windows Server 2008, and
for Windows 7
http://support.microsoft.com/kb/947821
If needed you can get free incident reports however the above should take care of it for you.
For Windows Updates - Free Incident Report
Go Here and Click -> Windows Update fails while scanning for, downloading, or installing updates
http://support.microsoft.com/gp/wusupport#tab3
For Security Updates you can get a Free Support Incident Report
http://www.microsoft.com/protect/resources/support.aspx
Hope this helps.
Rob - Bicycle - Mark Twain said it right.