Long time Windows user (for work these days), fairly long time Linux user (at home) and casual gamer here. I personally mostly played titles that were quickly supported on Linux so the switch gaming wise wasn't that painful to me. I just accept that the "best" titles probably won't come to Linux anytime soon (if every) and just play the games that exist. I'm totally fine with it.
I think Mint is a good option, that is what I have primarily used for a number of years. I have always preferred the KDE edition but that will be going away with Mints next major release. I haven't decided it I'll stay with Mint down the road yet, we'll see...
I think one of the major sore spots for games on Linux is graphics drivers. Mint has a really simple graphics driver installer, but the driver is not cutting edge. So if you end up needing the latest driver for your graphics card for performance or bug fixes, it is a little painful. The installers aren't quite as easy as in Windows, and they can be buggy if you are on bleeding edge. Unless absolutely necessary, I tend to stick with the driver that Mints driver installer suggests.
Normally I suggest the Virtual Machine path to getting into Linux, certainly look into it, but I think if you want to try it out for gaming, I would probably dual boot. But don't attempt to setup dual boot unless you are prepared to lose your Windows install, it's somewhat easy to goof up your Windows install when trying to setup dual boot.
Random info about my setup: Linux Mint KDE, I play games through steam. Counter-Strike, Portal, my kids and I play some Worms titles, Cities: Skylines and a few others. I just picked up F1 2017, which has been a great game. Just check out steam for which titles you may be missing out on and whether or not you can tolerate it.