If I have to choose I'd take gameplay without a doubt. Tetris has absolutely zero story but I do enjoy Tetris quite a lot. I'd probably not go within five miles of a game with the opposite amount of gameplay.
Gameplay is the core of a game. it's the unique selling point, what makes it different from books, music, films etc.
I do love a good story in video games but the gameplay greatly affects how that story is told. You can have an awsome story but if you tell it in a bad way it just falls flat. Gameplay also greatly affects the game world as it sets the rules for the universe, it decides how you move and interact with the world, what you can and can't do. It also greatly affects the player's connection with the playable character(s).
In short, gameplay is what ties it all together.
Now, I'm not saying that story should be eliminated, that it has no place in video games or anything like that. I do however think that gameplay should be the #1 focus no matter what kind of game you make. But that's just me.
