I can't close finder windows - finder reopens them
When I close a finder window, the finder menu disappears and then reappears along with the finder window. It looks like finder is crashing and restarting. This started happening after I downloaded a pdf and put it in a folder. Maybe there is a bug in the way finder is rendering the image of the pdf file at the top of the finder window?
How can I restore normal behavior of finder?
MacBook Pro, Mac OS X (10.6.8)