For novice or semi-novice, users wanting to try a libre distro, there's Trisquel. Trisquel 11 works fine, you get Ubuntu's 22 LTS' 'standard' software but it uses Mate as the environment. Pretty usable from the start. Trisquel Mini it's the same but with LXDE.

If you sadly need propietary firmware for wireless, install the Xanmod kernel and run it, then try buying a cheap Atheros 9k based USB device.

It's propietary, I know, but at least it's just for some kernel blobs on firmware, and Trisquel itself disables some 'bad' modules such as mei and mei_me by blacklisting them.

For Windows games, if your son/daugther needs that, at least run Lutris and install all of that on a separate account. You can always show him Xonotic or Red Eclipse. It might not have AAA graphics, but gameplay wise on Red Eclipse you can do crazy hops and parkour on arena matches.

Desktop wise, it's far faster than Windows 10 and 11, it won't install bloatware and lag like hell. No issues with Celluloid as a video player, and you can install VLC with two clicks. Icedove (Thunderbird) will work fine with most email accounts, seamlessly.

For developers and sysadmins, it has the same infra as Ubuntu LTS editions, so you will be covered.