I've been running Linux Mint for a few years now and it's been really good for me. Runs games through Steam and Lutris about as good as I've had it.
I've also run other distros like Pop! and Fedora here and there but they seem to give me more issues.
Edit: I'm a dumbass and forgot to mention the game I've easily played the most over the years: RuneScape 2 and currently Old School RuneScape. I love it. Lol
The biggest game for me in my childhood was Starcraft: Brood War. It got me into super RTS games, and even though I played it on the Nintendo 64 (which sucked in retrospect lol) it was the first game I really got into.
The next two games that come to mind were Super Smash Bros and Halo (specifically 2, but really all of the ones before 4 I played a ton of) just because these games were super easy and fun to play with friends and family.
And there were some honorable mentions like Phantasy Star Online: Episodes I & II and Star Wars: Knights of the Old Republic 1 & 2 and Star Fox 64, since these were also games that I played a ton of.