Reports on some forums are complaining that Windows 7 will not shutdown or reboot. An error message about permissions is presented.
Also beware that new nVidia 1600 cards as well as RTX 2000 cards also require Windows 10 x64. nVidia has posted this on their site.
Here at Hardcore Games, Windows 10 has been in use since it was an alpha. Today games run well with Windows 10 x64. Early on there were problems but every last one of them has been fixed.
With over 1000 games it takes a while to check them all. Occasionally flakey drivers are to blame. There are some problematic games that AMD and nVidia are both working with developers to fix.
The only games that do not run all that well are due to the DRM called Denuvo which imposes a brutal CPU workload that is far above the console.
Windows 10 x64 will run in 4GB of memory but with more the operating system performance rises rapidly. Best bet is at least 8GB to play contemporary games. The GTX 660 is generally the minimum video card for contemporary games but recently there have been higher system requirements.