Okay you got a few ways to get into Linux....
1. Virtual machines. This is probably the easiest way, get VMWare or VirtualBox and a Linux ISO and set up the VM
2. Actually making a bootable ISO and installing Linux on your physical system
For the second one you'll need to turn off secure boot however which is going to be a bitch to get to and turn off....but if you can do it....I'd recommend it personally if you want to ditch Windows.
Orca works perfectly fine with Gnome based desktops, I'm partial to the Mate desktop myself, I'd suggest it for everyone as it's easy to learn and everything is easily and logically laid out, you got your applications in on menu, places in another menu.
Games on WINE is a thing, you can run Windows programs with WINE and once you get that set up....it should run a good number of Windows programs.
For accesssibility again, Orca keeps on improving, and it's open source so you can view the code and make tweaks and help improve itt as well, unlike on the Windows side where things are closed source and tweaking closed source code is often viewed as hacking and/or illegal and/or piracy and/or <insert favorite hysteria here>
Is Orca perfect? No, but it's absolutely useable with Firefox or its derivatives....plus it comes preinstalled with most distros, so that's a plus.
Last thing....I've used both Windows and Linux and I've said it many times, on a laptop, Windows FEEELS slower, even if the numbers are the same.
Here's a few distros to get you started:
Why? It's Ubuntu, it has a metric load of stuff in the repos, and it's perfectly useable with Orca, but it will stop being supported at some point. That being said, upgrades are free. That being said, again, you're stuck with the software and versions in a particular version you download, 16.04 does not have the 16.10 software for instance, though there are ways around that.
Why? If you want to go the ultra hardcore geeky Arch route then there's Antergos or Sonar that, in the latter case is accssible Antergos which is an installer that simplifies the Arch install. Advantages of Arch? You get the latest software without waiting for it to be curated or added to a repo. Disadvantages? Bugs, Lots of bugs Oh and Sonar comes with the Gnome desktop by default
Why? Indie distro, it has a Mate and Gnome flavors that work fine with Orca and it's a midle ground btween the cutting edge of Arch, and the fixed releases of Ubuntu.
Hopefully that helps, I'd say Solus is your best bet as far as getting into Linux goes frankly, it's walked through how to install it on their site and it doesn't come with half the bloat Ubuntu's saddled with, plus you get put into a live session to try out Solus without having to go through a menu like in Ubuntu