I tried to change the icon on my ipod and before the icon could change the finder froze and i just had a spinning wheel so i went to force quit and relaunched finder but nothing happened, then i tried to restart but it wont let me, so i turned the computer off manually and when i started it up again its still the spinning wheen and no hard drives. i can use everything in the dock except finder what is going on? Can someone please help me?