I don't think my sister is unintelligent, but there is a certain lack of comprehension that I notice with her even though she is very clearly interested in video games, so I think throwing her into a game that isn't "Jump on the thing to win" would be irresponsible, at her age I was playing through SNES games relatively competently, they were hard and took awhile, but I knew the basics and figured them out, I never had Chrono trigger though on SNES, I played it years later, along with this Japanese RPG DBZ game that was really fucking awesome and oddly addicting.