Hello, I hope there is some help for me, but after spending the day reading and experimententing I am doubtful. I have just recieved my 27" iMac, which I love, to replace my again MBP from 2006. I have been running Snow Leopard and years ago had purchased Window Vista (32-bit) to use in boot camp. What I would like to do us upgrade my Windows Vista to Windows 8 for use in on my iMac. I do have a exeternal disk drive. I have installed a friends version of Windows 7 that I can use or 30 days in hopes that it will help with the process. I have tried booting from my Vista disk, but can't move the curser to complete the instal on the iMac. I spent as much money as I could on the compter itself with little left over to buy new software (not realizing I couldn't keep using what I already purchased). Can I upgrade my Vista to Windows 8 and move the whole thing onto my iMac? Is there any way to get Vista onto the iMac and then upgrade to Windows 8? Can I install Snow Leopard, then install Vista, then upgrade to 8, then move back to Mountain Lion?