The minimum requirements don't really mean much if anything. All it does mean is that the thing will run but very, and I mean, very slowly. The rule of thumb is to always have hardware that meets or exceeds the recommended hardware for game play. This will mean you will enjoy the game a lot more without long load times and some good quality graphics.
In your case you may very well be able to play Vice City but graphics will be very poor, load times will be long, and you may end up beating your machine before you ever finish the game.
