It's honestly difficult to know where to begin in reviewing Saints Row 2. There are so many excellent aspects of the game I doubt I'll be able to cover them all. The story follows on from where Saints Row left off. You begin by waking up in the hospital wing of Stilwater Penitentiary, where you have been in a coma since the boat explosion. A fellow inmate called Carlos helps you to escape and it is during this escape that you learn the controls of the game (which aren't especially complicated). Once you have escaped from prison you have to rescue fellow Saint Johnny Gat from his own trial, and recruit three lieutenants to help run the Saints. After this point the game opens up a lot more and you can access all of the side missions as well as the main story missions. In order to be able to access the main story missions you have to have enough respect, which can be earnt through side missions, driving dangerously, and generally acting like the tough gangster you invariably are. A lot of the fun from SR2 comes from these side missions. My personal favourite is Insurance Fraud where you are tasked with hurting yourself as much as possible by running into trucks and throwing yourself off of buildings.
The main aim of the game is to take over Stilwater, and this is achieved by eliminating the other gangs: The Sons of Samedi, The Ronin and The Brotherhood, each with their own maniac at the helm. SR2 is a really fun game, and the main reason for this is that it doesn't take itself too seriously. It doesn't try to be a hard gangster game, and instead it serves as an excuse to run around in your underwear shooting rockets at police cars (if you so wish). As a result it's a lot of fun to play, and I can imagine that I will play it through again and again in the future.