This is actually a difficult year for me to decide. I love the point and click adventure genre (with high focus on humor) that The Secret of Monkey Island made popular.
Usually I judge a game based on how likely I am to pick it up and play today. By that metric Super Mario world is the winner since it is still a blast to play.
But I feel that in the case of story driven games that metric is not as fair. The game will pretty much never be as good as the first time it is played since a majority of the enjoyment comes from not knowing.
The vote goes to The Secret of Monkey Island this time. An exceptional game with a massive impact that might be the first time a video game made me laugh out loud something only a handful of games have succeeded in, can only think of Conker as another example even if Ace Attorney and the Mario and Luigi games came close.