I know what you are thinking... hold down option. Yeah, that does not work. I just started using my iMac after a bit of time and now it only wants to boot to Windows. When I hold down Option at bootup, all that happens is the grey screen is there longer, then it will just go straight to Windows. I've tried both option keys and even Command + R but I still end up peanuts. This is just one of the many problems I am facing with my 3 machines Thanks for any kind of help.