Ok try this, uninstall windows essentials.
Reboot and create a system restore point.
Download Link Removed and run the registry cleaner making sure you create a back up of the original registry when prompted.
Reboot again and then look in the start menu for command prompt, right click on it and run as admin. Type:
sfc /scannow
Press enter and await results
Reboot once the scan has finished and then try installing the latest version of Essentials/Moviemaker.
Normally I wouldn't recommend using a registry cleaner but as we are getting no where it might be worth a try.