If my Gengar fails to put another Pokemon to sleep, I get ticked. The chanting of a priest in Age of Empires drives me into a frenzy. I scream, swear, and generally act in a manner that would be inappropriate in front of your mother or the Pope. I have a hell of a good time. We are fighting a war, after all.
Brood War picks up almost immediately after the end of the original game's storyline.
You may recall that in the original Starcraft, the Terrans were a colony group, more or less forgotten by the home planet. The UED not only wants to reconquer the colonies, they want to enslave the Zerg Overmind, grab Protoss technology, and probably steal their neighbor's Sunday paper while they're at it. Like the humans in Starcraft, they pretty much exist to screw each other over. In terms of game play, there are two major additions in Brood War. One of the things I loved about Starcraft was the subtleties of each unit, the way they could be played against each other to give you a toehold which could be parlayed into a greater advantage.