For me, probably the original Super Mario Bros for the NES. It was so much fun and it was such a simple time. lol Never mind, Mario Bros 2 and 3. Yup. No no...the first 2 games in general coupled with the Super Mario Bros Super Show...total nostalgia trip.
I remember when I first played OoT. I received the very first version (since it was preordered) for the N64 for Christmas of 1998. Loved it!