I have a nice selection of console systems.
Atari 2600+5200
Nintendo, Super Nintendo, N64
Dreamcast
Playstation and PS2.
Xbox
The Dreamcast was surely the easiest one to play copied games. Had no protection and would boot up every game copied. BTW I have about 150 games just for the DC.
Back in the day the Dreamcast was ahead of it's time and had a very nice selection of games. I am not sure of the exact models that would or could not play copied games.
I have 2 Dreamcast systems and they both play fine. I could give you the model #'s if needed, so you know what to look for.