Training recommended?
@gollux - If you are responsible for a Windows 2012 R2 server and it is installing patches and rebooting overnight without your knowledge or approval then perhaps you should consider some basic training on the O/S you are managing.
I had a co-worker who often used a phrase in meetings (going way back to the Windows NT days) to describe the difference between machines that blue-screened frequently compared to ones that ran for months at a time with no issues: "Any idiot can run setup.exe". If you are moderately educated as to the capabilities of your OS and best practices for operations you will have much more success regardless of which flavor you choose to run.