Not sure about Belarc there are several out there to find your Product numbers. However unless your going to upgrade to Pro or MC, download the ISO from Microsofthttp://windows.microsoft.com/en-us/windows-8/create-reset-refresh-media unless you have pro download the Windows 8.1 Core 64 bit, on a clean install it will pick up your embedded Product Key.
a 256gb SSD is optimum for your OS drive. You get the best speed and still small enough to make Images quickly. You will even have plenty of room for your major program For Me I have Office 2007, CS4 and all major software on my C:\ 256 GB Samsung 850.