Programs shut down automatically...

I downloaded the 25 most recent critical security updates for windows using auto-update. Once they were installed and windows was restarted, Task manager and several other programs no longer work. when I bring up the task manager it comes up for a split second then seems to close automatically. The same goes with my nortan anti-virus, my internet program, and a few others.

Now, I did a system restore to the time before the updates and everything worked super for about 4 days. Then suddenly while I was browsing the net, it started happening again. I didn't download anything those 4 days and the problem seemed to come back spontaneously. Though this time, Task manager works.

Any suggestions?