If you already have the time and you have figured out what files are affected through the windows update, then you can use the "Restore Previous" versions of file/folder feature of Windows 7. You can use this feature to recover accidentally deleted files. Windows 7 creates these copies for you through the System Protection service. So ensure that you turn it on. Right-click on any folder and you shall find the "Restore Previous versions" option. You would be presented with the list of previous versions and then you can either choose to Open/Restore the version.
If this is not the case, then type "rstrui.exe" in your run menu, and launch the System Restore wizard. Press the "Next" button from the first screen, and choose a restore point that pertains to the date before the installation of the faulty update. Follow the onscreen instructions and reboot your machine.
Hope one of these helps.