Microsoft patches – happen every 2nd Tuesday (until this policy changes with Windows10)
https://technet.microsoft.com/en-us/library/security/ms15-nov.aspx
Ms15-112 through MS15-123 are various patches that need to be patched, just remember to not download Windows 10, or at least not to install it until you are ready.
A full Windows Operating System upgrade is not so easy and actually might not be a good idea on some older machines. It would be wise to backup the files before any upgrade is accomplished -In this case I would actually recommend to stop auto-updates.
Unfortunately Microsoft has started to automatically update any system with auto-update on. For those of us who have to run Windows computers this is a bad idea.
Windows 10 has a lot of privacy problems.
http://www.techrepublic.com/article/the-windows-10-privacy-debacle-five-big-issues-to-consider/
It takes quite a bit of effort to remove or reduce the privacy that should be in Win10.
this reminds me of this Cyberjoke from weeks past:
this is also true:
Programming is like sex:
One mistake and you have to support it for the rest of your life.
Remember that when you are thinking of upgrading an old computer to Win10. It may not work as well as you think it will. Having a backup plan and a lot of time is a good idea.