only thing i think of when i think "farmville" (aside from harvest moon) is this
http://www.ninjapirate.com/article/farmvilleif i were to make a list i would do something like this
pong - probably first game that people could play at home
tetris - spawned an entire genre, and probably paved way for logical games
mario/supermario (whatever it was called initially) - platforming games
resident evil/alone in the dark - laid out foundations for horror/survival horror games.
doom - multiplayer fps, also along with wolfenstein 3d and other games from that time, started shareware games for people to try out.
quake - first game that offered such incredible modding potential, and introduced the console. probably the first 3d game that separated the actual engine from the game logic, allowing users to modify the latter.
fallout - a good rpg. a post apocalyptic setting. retro style. all these elements are now often present in video games.
max payne - bullet time, and one of the first shooters with a really good story and mood.
metal gear (msx) and metal gear solid - probably first games that oferred stealth, and non-violent approach.
dungeons and dragons - first game that had a boss opponent
gran turismo - one of the first games that really strived toward realistic racing. maybe not the first one, but that one is remembered as one of the first.
quake3/unreal tournament - fps games that completely ditched single player experience and pushed forward online gaming. i hate them
final fantasy 7 - it was the game that opened the western market for japanese rpg's. also called "the game that sold the PlayStation" - does that require an explanation?
un-honorable mentions :
daggerfall2 - a game that people waited for, and was ridden with bugs and glitches. and never really got fixed. we have lots of games following that "trend" nowadays. they just don't make the games like they used to.