Kotaku posted an article recently about how it's difficult explaining some games to people who aren't gamers. I constructed a comment in response to this, and I liked what I said, so I'm sharing it here.
The article can be found at http://kotaku.com/5548524/video-games-ive-let-you-down. My response is as follows:
Everyone understands gameplay. Everyone understands story. Each of those is easy to understand by itself. That's why games such as Tetris, Mario, and Grand Theft Auto are so easy to talk about. Tetris has no story. Mario's can just be ignored. Grand Theft Auto's story can also just be ignored, like many 'sandbox' games.
When these two aspects become entwined, inseparable, things become difficult. It is like trying to explain a 3-dimensional world to a square (a-la the book Flatland). These two dimensions, gameplay and story, combine like two number lines to form a cartesian plane which is infinitely more complicated than the sum of its parts. Unless you play video games, explaining this two-dimensional space is difficult because most people have only experienced the two concepts separately.
Fallout and Bioshock are also unique in that the main character acts like a paint brush who paints upon the canvas that is the setting. Although they are major players in the story, they act out your wishes. You aren't observing their actions, you're controlling them. This complexity only exists because of the combination of interactivity and story that video games provide. It allows the players to see and feel the consequences of their actions, and gives video games a new layer of depth.
Finally, people expect video games stories to be stupid and infantile, but in reality they can express very complicated concepts. However, when you tell people "It's a game about the failure of Randian Objectivism", they are going to look at you like a baby with a briefcase, and you suddenly feel awkward.
It's not a problem with games, or the nomenclature associated with it. It's a problem in that other people just don't understand what modern video games are. On the surface, all they see is game, and it's what they expect. However, there is much more to it than that.