content: If your granny only needs to run a browser and type letters in a decent word processor, the unequivocal answer is yes, at least if she's already able to use Windows.  Most distros will do a fantastic job of this right out of the box, and if she's using a distro designed for end users and not a whiz-bang, cutting-edge computer, it'll probably make all the right decisions during installation and come up with no problem on the first try.  I've been hearing for years about people swapping out broken Windows installs for Ubuntu or Mint for elderly relatives and having fantastic success, and from what I've seen, I believe it. Things get more complicated from there.  Linux is great, but it has some very serious gaps for some markets.  These seem to fall into the middle of the spectrum in terms of uses.  For complicated uses where you need something heavy-duty and able to keep up with the computer science majors, Linux is great.  If you need an appliance where things "just work" or something to run a relatively standard set of applications (specifically a web browsers, LibreOffice, and other "standard" programs in distros) and someone else (specifically the manufacturers) set it up already, Linux is great. If you want more middle-range desktop work or a light, stupid-simple server, things get more dicey, and you might be in for a rough time if you aren't willing or able to learn (and I do acknowledge there are people who have good reasons not to want to learn Linux).