I have an older macbook and was running os 10.5.8. I wanted to update my os to Snow Leopard but since i couldn't find it through Apple themselves I resorted to downloading a torrent of it (yes, I now realize just how stupid a mistake that was for something like this). The install went okay but when it asked me to restart it went to a gray screen asking me to restart again. ("You need to restard your computer. Hold down the Power button until it turns off, then press the Power button again.") Every time I try to start/restart it that is all that comes up. What is wrong and how do I fix this?