To quote Newsweek, Windows 10 is out and “you’re probably going want to refrain from upgrading right away.” A couple of good reasons: it’s Microsoft — so it’s probably full of bugs and problems. Wait a month, there’s no rush. Second, your computer is probably working the way you want it to (more or less), so why mess with that? Guaranteed there will be some SNAFU in the upgrade and you’ll lose programs or settings.
If you’re using Windows 8 (rhymes with Hate) and are desperate for 10 just to get a start menu, install the excellent, free menu from www.classicshell.net — it works great and gives you back the control you lost over your desktop.
If you are running Windows 7, arguably the best OS Microsoft has ever produced, why would you want to mess with that? Things work. It’s relatively robust and mostly trouble-free, and MS says they will support it for the next few years.