In the signt of windows telemetry which I hate, I'd recommend either Windows 10 Enterprise (standard or LTSB), or Education, or Windows Server 2016 - in these you can set telemetry level 0 in the group politics, this effectively disable any background stuff except very basic like anonymous ID and system install data, and if Windows Defender disabled, no compat data or system scan data send to MS.
For gaming in explicitly Steam or classic games, I'd rather recommend Windows 8.1 Pro, it's MUCH more polished, has better compatibility, more stable and in general have more in line with previous versions of Windows, but has the same advanced system servicing programs and almost as new core as Windows 10.
