If this is too broad to really say, let's say proudest achievement per system.
For me, I would have to say:
GameCube/Wii: Metroid Prime 2 Echoes hard mode 100% completion playthrough
Xbox 360/One: 50,000GS mark
PC: World of Warcraft LoreMaster meta-achievement (As of WOD)
Most Helpful Guy
The last of us multiplayer, which is a pretty difficult multiplayer to begin with. Anyway we were getting our asses kicked in interrogation mode and were almost defeated, but I stood back with my shotgun and defended our box and ended up getting almost 20 defensive downs and executions, giving my team enough time to gather our interrogations and get to their box to win. It was by far the most badass thing I've done on a game. And for anyone who hasn't played that game, 20 downs is a lot, most good players average about 7 per match. So to get 20 is quite the accomplishment.
Most Helpful Girl
Um... does Zoo Tycoon count as a video game? Or the Sims?
'Cause if not... then I've never played one.