The Grand National at BPB When I was about 7 when it was just a lap bar + grab rail with no seatbelts I think, can't really remember anything before it although I'm sure there probably was, I'd been addicted to the original RCT and even the old MS DOS Theme Park game from the day I was born pretty much.
First coaster with inversions? I dived in at the deep end and did Dragon Khan on the front row when I was 13, still to date one of my favorite steel coaster's and absolutely wipes the floor with Nemesis.