dtgreene: What software will you install on it? This includes, but is not limited to:
* Linux distribution
* Desktop environment
* Game launcher (like Lutris, Heroic Game Launcher) if you choose to use one
Also, it would help if you would explain why you would make your specific choices.
Debian 11. For stability reasons and preferring LTS releases.
XFCE. Lower on resources, customizable.
No game launcher, no use it in it for me.
WINE, Firejail, gaming emulators plus firmware/drivers: Too many games are Windows-only, installing Firejail with custom configs, isolation, is important to surely keep the host safe of whatever is going on inside the WINE environment; The emulators is for Nintendo Switch and other staff like that, should be pretty secure; The firmware/drivers from the non-free section are not installed by default, always need to fix.
Nothing else is on, it's a gaming computer, not for browsing the Internet nor for any other tasks.