For gaming, RetroPie is a cool solution (it doesn't require raspberrypi).

I have a setup using HP Pro Mini 400 G9 that boots directly into EmulationStation. It's perfect for playing with my kid, covering everything from NES to more recent consoles, and also Steam and Minecraft (via https://github.com/minecraft-linux/appimage-builder/releases) if needed. The offline aspect of non-steam games is a big plus for easier parental management too.