That is the OS I use to develop Mach with so it is the preferred OS. XP is dead, Vista was crap, nobody knows what Windows 8 was, and Window7 was good but the world has moved on. There are probably not a lot of Windows 7 installations out there because MS offered the free upgrade to Windows 10.
And of the different versions of Windows 10, I like Pro the best. With Windows 10 Pro, you can postpone updates for a year and the bi-annual refreshes for 6 months. But still, not connecting it to the internet is the primary means of keeping Windows 10 from automatically updating you at the worst possible moment. But on an initial installation, I would suggest updating the OS fully, then install Mach, and then never let it see the internet again (unless you want it to update).
Steve