Win7 Updates vanished, can't download

The most bizarre situation ever for me: All of my scores and scores of Windows Updates are gone. Checked System and Security, view installed updates: No updates installed in this computer! Checked Windows Updates in All programs: nothing. My last Belarc Advisor profile listed countless KB updates, but the latest printout shows absolutely none. For several weeks, the exact same updates notifications in the system tray say two critical should be installed. I've installed them about 20 times: Security Update for Windows 7 (KB977165), Security Update for Windows 7 (KB2393802). I've customized the system tray to "show icons and notifications" but only the same two are there! I do not install them automatically; I am notified and then decide.
I've tried to download all required updates directly from the Microsoft security site but am told to go through Windows Updates, all programs. The only ones that show up are the above two. Bottom line: There are no Windows Updates on my machine, and I can't install any. Your ideas will be greatly appreciated. ec

I have tried EVERYTHING including reset, the ideas you all have given, tried to install directly from Microsoft, you name it: I feel certain there is nothing more to do to be able to download and install updates for Win 7, dozens of which were in my system before they vanished.
I have a Windows repair disk I created. Should I use the repair disk? Should I reinstall the OS? This is the weirdest thing ever to happen, the only problem I've had for which there appears no solution.
The same two update notifications appear in the system tray which have been downloaded about 20 times, but still appear. This is frustrating beyond belief. ec