Unfortunately, a large percentage of computers are still running XP. And if the computers are not modern enough, they might not be able to run the crappy Window 8.1.
But MS has a link to some nifty brand new computers.
8.1 is a better version of Windows 7. All a person has to do is set it up to use the desktop by default.
My suggestion for Microsoft. Make every version of any M'soft operating system available (legally licensed) over the web for a small licensing fee. Then, when one needs to upgrade hardware due to machine death, have the new computer (running Windows 8 (or later for the future)) set up the version the buyer of the new machine needs to run for legacy purposes, in a virtual machine.