There are few games out there that really let you play them the way you want to.  Few games let you make bad and even worse choices but GTA4 is all about options.  If you think that this game is a cop and/or prostitute killing simulator you would be very wrong.  Sure you can kill anyone  in the game but if you do prepare you the game to go medieval on your ass.

At it's core GTA4 is a story of an immigrant coming to America to live the dream but can't seem to shake the troubles he left behind in the old world.  The game has an incredibility good story and will allow you to build meaningful relationships with the other characters in the game.  In the end your past will hurt one of the characters you're closest to and there is nothing you can do to stop it.

The game creates a real live city, Liberty City, that can keep you entertained for several hours.  This sand box game has tons of side missions and a long gaming experience that challenges you to complete the main story in under 30 hours.  There's just so much to do and see it's amazing to play a game with so much depth.

The online multiplayer is a nice addition to the game but still that's not why people play this game.  They play GTA for the story and the open world where you can choose to be as vile as you want to be.  It is interesting to play as a criminal but you still have the power to play as good or evil as you want without the social detriments in other games.  This is by far the best game I played in 2008 based on it's single player mode alone.