My list of stand out all time games in my gaming life...
Gauntlet. 1987. Spectrum 48k. Great fun and playability. I remember playing with a friend all day Saturday, Leaving the game paused running over night and continuing playing all day Sunday.
Super Mario 3. 1988. NES. Brilliant fun and playability. Still play it randomly now when I can.
Shadow of the beast. 1989. Amiga. Blew me away at the time.. incredible game! Incredibly difficult game!
The killing game show. 1990. Amiga. Another amazing but little known game.. Graphics. Music. Playability. Amazing.. still love having a go now.
Gran Turismo. 1997. PS. Best driving game ever at that point. Just wow.
World of Warcraft. 2004. PC. Along with first two expansions was a great game and good fun to play with friends. Was a game like nothing else I'd played at that time.
Skyrim/Witcher/Fallout. Xbox/PC. Just superb games and series. Some of the best games I've ever played.
There's plenty more but these are the top top ones for me.