Sitting on a couch in the basement, table thing in front of it, little CRT on top, PS2 plugged in, playing Star Wars Battlefront ( either 1 or 2 ).
Either that, or being on a different couch in the same basement and playing Sonic Mega Collection, the game that turned me into the big Sonic fan I am today. That game, specifically if there is a marathon of one of my all time favorite shows on TV that I can switch from game to cable and back. Well, we had a weird CRT with radio, so press the button twice for game or whatever else you had plugged in, but that was a very minor thing. Happened once during a pokemon marathon middle of the day middle of summer vacation and never again since.
Definitely a tie between those for me. I don't necessarily try to reach that high because I know I'll never be able to recreate it unless I can find those exact couches, design wise, those exact TV models, and buy my childhood house and remodel it to make the basement look exactly like I remember it. That, or get a replica that is uncannily close to my memories.