I bought a new mac mini in july. The second day I installed a genuine copy of vista 32 bit. To switch to vista I hold down the alt option key when the mac is starting up. In a few seconds a gray screen will show up with two options: Mac and Windows. Now about 5 separate times, the mac froze at this screen after I selected one of the two, usually or all the time I believe I selected windows. I waited but in the end I was forced to force shut down the mac. Just recently I got rid of vista and installed Windows 7 ultimate 64bit and it just did it again at that screen. Why is it doing this and is this really bad for my mac, I had no other choice.