I have a 6 month old Toshiba Satellite laptop with Vista as an OS. It is slow, will not respond when i ask, and is just an over all pain in my a--. I recently purchased Windows 7 proff for a completely crashed laptop. 1st, how many times can i use this sofeware, and how would i go about upgrading Vista to Win 7 on my Toshiba, if i can use this software more than once.