After 10 minutes with nothing happening, I hard shut down the computer again. I held the power button down until the shut down menu popped up, and I clicked 'Shut Down.' Screen went to black with the mouse curser still visible, stayed that way for about 5 minutes, then became the spinning beachball. Restarted the iMac and logged in normally, but at startup Finder and the menu bar were unresponsive. Had to hard shut-down with the power button. Relaunching from the tray icon didn't do anything. Finder stopped responding and prevented me from shutting down properly.
Today I had a Finder crash (infinite beachball) while emptying the trash.
