The oldest system I have would be the NES. My brother received it sometime before I was born. I’m just holding onto it for him, though - it doesn’t get played right now. I actually intend to clean it all up and retrobright it before sending it back to him… eventually… The oldest system I have that still gets occasional use would be my Gameboy Color, which I received, with Pokemon Red, for Christmas when I was 8 or 9. Unfortunately, I need to find a better plastic polish, to take some light scratches out of the lens, and until I do, it will remain disassembled… I’ve also been contemplating using the board for a complete boxypixel overhaul, but there’s something about still having my full original GBC that I’m having a problem getting over…

IDK. Most of the early games were actually pretty entertaining. I fairly recently played sorcerer’s stone on the gbc, and it was still pretty fantastic.

I haven’t played most of these, but I will gladly add an endorsement to the early Harry Potter games. They often only tangentially related to the movies, but they had some awesome mechanics, and played into the full story really well.