My wife: The first time I played the sims, I put the refrigerator with the door facing the wall, and all my sims starved to death.
Also, the first time a sim of mine had a kid, the mom died. The dad wouldn't stop crying, so the kid got taken by social workers. Then the dad starved to death.
Me: Oh, I'd have to say accidentally nuking a friend in C&C Generals. With all my four nukes at the same time. He was not amused. We lost that game.
Oh yeah. And failing to an easy mode computer in Warcraft 3....
A LOT. Like, over and over. To the point where I felt proud if I could take the easy mode computer out.
God, the shame of it all... I'm usually good at RTS games, but Warcraft 3s computer is just...unfair.