I've been running Linux exclusively at home for quite a few years now. Aside from being free, I find it just works better than Windows (for me, at least). We're running Linux on four computers. Eight if you count Android tablet and phone, EasyTomato router, and a desktop I built out of old spare parts that I plan to sell.
I've tried quite a few flavors of Linux, including Gentoo, Slackware/Slax, Ubuntu/Xubuntu/Kubuntu/Lubuntu, Mint, Fedora, and Arch. Arch Linux is by far my favorite so far which I'm running on three computers with Xfce. The Ubuntu derivatives (including Mint) are probably best for an inexperienced user, though I found Mint to run very slow on older hardware. Fedora + LXDE was much better on old hardware and still newbie friendly.