Long "lag" after taking a screenshot.

I press Command Shift3 to take a screenshot of the entire screen. By default, it goes to my desktop, as it should. The problem though.. Right after pressing the three keys, I hear the camera-shutter sound effect for the screenshot, but after that for about ten or so seconds, everything is completely locked up.

I can still move the cursor around, but trying to do anything with it results in nothing, sorta. After the "lag" ends, whatever I had done with the cursor during that time suddenly happens, such as moving windows around, or clicking on things.

I don't get a spinny wheel during that time either.

Any ideas as to what could be going on?

I'm running a clean install of Leopard that is two days old.