I have HP laptop with a genuine windows 7. I want to format the whole system and reinstall windows 7 again. the HP tools are not working now after some windows updates. So I couldnt create a recovery disk. All I have is a genuine key. How can move further on this. where I can get Windows 7 home premium, so that i can install it and authenticate it with my key. is the torrent downloaded windows 7 is trustworthy?