Whether you started with a 2600 and a joystick in your hand, an N64 with a blistered palm or building your first PC in your teens, what is that one video game you've played at some point that to this day sits at the top of your list.
The original Legend of Zelda on the NES. It fully captivated me as a child. I remember taking the game map to school with me and my friends would circle trees that could be burned or rocks that could be bombed. Such fond memories.