OK, lets get this straight once and for all. Because I hear an awful lot of bullshit about Win10, MS playing underhand, and "this is what my mum's dog's brother's best mate's girlfriend heard down the pub".
MS want everyone on Windows 10? Yes, absolutely.
They WILL ensure everyone is forced on to it? Nope. They provide AND DOCUMENT a list of official options to prevent it being deployed. They do this because the one group of people MS really do not want to piss off badly are medium/large companies, and they really don't want to get on the wrong side of head of these IT departments. So MS HAVE to ensure a very robust method of doing nothing.
The Group Policy method was publically published several months ago, and was available privately before then, but the internet is full of unreliable wank about uninstalling updates to prevent it based on flawed logic by people who think they are smarter than what they are.
MS were really only putting the update block in place for enterprises, so were slow to publically publish the options, as most enterprises would use Systems Center or WSUS to provide updates, until this year, neither could deal with a Win10 upgrade. I believe even now, domain attached computers will still not upgrade (would need to check).
MS's strategy for
Windows patching has changed from a full matrix more towards the Apple/Android style of only patching the latest. This partially happened partway through the life of Win8, and has gone all in with Windows 10 - so you'll see the occasional huge update, then cumulative updates to that big update, with no/few standalone
Windows patches.
For non business users, there probably isn't much reason to refuse a freebie upgrade to a legal
* version of Windows 10, as to be frank, it runs on virtually all things that could run Vista (Win10 is ultimately just an enhanced Vista kernel) as well as the original OS, with very few compatibility issues. However, I do believe that should be the user's choice... ...to an extent.
So, in essence, if you don't want Win10, use the officially documented ways to block it, as these will be robust, as they are built in order to really not piss off the purse strings. Thus, can be relied upon. Unlike most of the wank to bypass it that you find on the internet - I'm just the stupid kid from the local comprehensive, but even I could see that none of them are likely to work for any length of time.
* Including all those dodgy Windows 7 Ultimates, which one of the channel rags reported that MS were saying a huge number (like 90%

) were illegal copies, and that it is trivial for MS to decide which ones if they wanted to... ...maybe they will once (if

) Win10 free upgrade closes...