Windows 7 Infinite Updates (not boot loop)

First off, I'd like to apologize for not knowing exactly how to go about describing my issue, although I promise to do the best I can.

I guess my first problem was forgetting to write down the day this issue started happening, because that would have helped me narrow down the problem, I'm sure.

Also, I'd like to note that I believe it's something to do with Microsoft Silverlight.

Anyway, every time that I turn my computer on, it logs on with no problem and doesn't have to install any updates. However, every single time I turn my computer off, it "installs" updates... and the same ones are available every time my computer restarts.

Here's a screenshot of all of the failed updates... so many things fail. [CLICK]
EDIT: Just noticed some repetition in that image... "optional" updates are always successful, "important" updates always fail.

Here's another image of something I get with nearly all updates I try to install (Silverlight/MSE/etc.):

I also just tried installing 4 new updates and got error codes 66A and 80070643.

It seems as if there's some error with every update I attempt to install.

drxthirst
Have you considered a System Restore point PRIOR to these problems occurring?

The error code 80070643 is a generic error that basically states that an problem was encountered by Windows Installer.

Two links for you to peruse to see if they may be of help.

You receive error 0x80070643, error code 0x643 or updates may be re-offered when you try to install .NET Framework updates when using Windows Update or Microsoft Updates

Error code "0x8007066A" or "66A" when you use the Windows Update or Microsoft Update Web site to install .Net Framework updates