multiple odd problems with windows

I'm having weird problems after running a registry cleaner. My WIndows Update does not work, even when I go straight to the MS site. When I do that it says I need to install active X but there is no information bar at the top of the screen like normal. Also my Windows Media Player does not work but I can't reinstall it because the installation fails. I think there is something wrong with my Windows Installer, but I can't tell. Also I tried to do a system restore to before I ran the registry cleaner but that doesn't work either. ANy help would be GREATLY appreciated.

Run System File Checker. Start - Run - type in "sfc /scannow" without the quotation marks. Have your Operating system installation CD available in case SFC needs to replace any missing or corrupt files. Best Regards