Blinking menu bar, icons on desktop and Finder windows.

This happened after I restarted the computer for installing software updates. The only thing that didn't blink was the dock. When I open an application, it blinks as well, but a little slower, so that gives me time to click around. Even shutting down/restarting is a problem, since the menu bar blinks so quickly that I couldn't click on it. I had to hold down the power button to shut down.

I tried creating a new account and logged in. Everything remains normal in the new account.
I went into Library>Preferences, deleted the file called "com.apple.finder.plist" and restarted. It didn't work.

Is there anything else I can do? I really don't want to reformat my mac and lose all the applications installed.