I highly recommend a -buntu variant of your choice (xubuntu is my favorite) if you're just starting out with linux. It's much easier to google "ubuntu <problem>" and get an answer that works, because ubuntu is definitely the most-used distro. Linux mint is based on Ubuntu so you're probably fine there too.

There's definitely a learning curve with Linux but after you've become familiar with linux you start to feel like you have much more control over your computer than you would on windows. I've come to absolutely love the command line, ssh, and others - it's just so convenient.

I highly suggest dual booting with windows as well, just try to use linux as much as possible and see if you can do everything you need to. Remember there's things like Wine that work for lots of programs and even old games. I don't know which old games you had that didnt work, but Wine's improved a decent amount since pre-Unity. I'd try those again, but yeah those games still might not work.

Edit: also, hardware support is SOO much better nowadays than it was in the pre-unity days, i think you'll find your hardware works a lot better out of the box now.