One of my machines automatically upgraded itself from Win 7 to Win 10.
Seemed alright at first, but then I found some of my carefully organised files in a tangle and a lot of small to medium niggles that took a while to put right.
Downloaded a Win 10 image and did a straight install rather than an upgrade - blessing the fact that I keep my data on a separate drive from my operating system (in
all OS'es). Much smoother.
But Windows still sort of expects you to to have everything under one roof as it were and it took a lot of farting around with links and junction points to get it all kosher.
And as for getting rid of that pesky Windows.old folder - phew! - had to do some mega fiddling to get rid of that - lots of permission problems....
But all in all I quite like Win 10 - especially if you install Classic Shell - [
http://www.classicshell.net/] which is completely free and makes Win 10 look and behave in a civilized fashion (none of those damn panes unless you want 'em.
Mac
[But I'll certainly hold off on the Anniversary upgrade - which is even now still really a beta release though they won't tell you that]
PS: If you want to stop Win 7 auto-upgrading itself you can tweak a few things in the Registry or spare yourself the trouble by installing the completely free GWX Control Panel [to be found at [
Ultimate Outsider - Software Downloads] which does the job for you very nicely. But I guess the free but forced upgrade is over now - you'll have to pay for it. Best plan is still to start with a clean Win 10 install though and not upgrade Win 7.
An even better plan is Linux Mint or one of the BSD flavours....or go over to Apple there my upgrade from Lion to El Capitan (skipping Mavericks) was smooth as a tomcat pissing on glass....
Ahem!