I have used Win10 and dont like it. We are still on Win7 in my house and we arent moving off of it till we have no choice. There is all kinds of odd stuff with the interface, they moved things around for no reason. You have to wonder what they were thinking about.
Regardless you can turn off the Windows updates via software. There are packages that let you regain control of the machine. Read this:http://windowsreport.com/best-windows-10-privacy-protection-software/http://www.ghacks.net/2015/08/14/comparison-of-windows-10-privacy-tools/
From what I have seen in the past few weeks I think all the OS's are compromised by the intelligence agencies. But with proprietary systems such as OS X and Windows you really have no idea whats going on. And thats just the way they like it. Plus they are bloated.
I have had Ubuntu 16.04 LTS on an older HP laptop for about a month now. Frankly after using it for a month there really is no reason to use Windows. 99% of what most people do on a computer can be done on Ubuntu. That means: surfing the web, reading email, music library and watching videos. Ubuntu does all of this with ease. On this old HP laptop Ubuntu is far faster than Win7.
Most people barely use MS Office at home so why not use Libre Office or the Google products. I had a fear of both. Guess what? The fear is completely unfounded. It reads my resume and spreadsheets. Are they as sophisticated as MS Office, NOPE. But for what most people do with MS Office, LibreOffice and Google are good enough.
So what do you need Windows for? NOTHING.