Last boss fight of MGS4. MGS4 SPOILERS!!!! Playing REX in Shadow Moses, the "easy bake oven" before the Ocelot fight (holy ****, that was emotional)
GTA IV. Taking a taxi ride across town for the first time WITHOUT skipping.
100 ninja fight in Ninja Gaiden II. Good lord, that was ****ing awesome.
Call of Duty: Modern Warfare 2 had some pretty memorable moments in its single player, most notably -the ending scene. Multiplayer in MW2 was also the best multiplayer (IN MY OPINION) this gen because it was so broken that it was strangely balanced. Best maps in the series too.
DayZ had some crazy good moments too, but that's because I try to roleplay and not be a PvP ass clown.
"Your" = Possession | "You're" = You Are | "Their" = Possession | "They're" = They Are | "There" = Position