I have copied 35000 photos from my I mac Hard drive to an external drive and have backed that up to another external drive. I went to delete the original photos from from my hard drive, missed the trash can and inadvertently dropped them onto the desktop. I couldn't then stop them from copying to the desktop so I cut the power and re booted but the computer continued to copy from where it had left off. The computer has now completely frozen with 35000 photos on the desktop and I am unable to do anything, even shut down the computer. I would be most grateful,if anyone could offer any suggestion that might help, many thanks in advance.