first online service I had access to was Prodigy, via a 386sx with 2400bps modem. I'm not sure if their service even had connectivity with the wider internet at that time. But I was 11, so naturally the first thing I did was troll their helpline with a question about where babies come from.
I remember The Dump, they had Genesis roms for a while but were taken down after a complaint from some industry association.