Single-player
There are three main parts to the single player game: Kudos World Series, Arcade Racing, and Time Attack.
In kudos world series the player has to complete a series of races in 14 different categories of car. The player begins with just three cars in the Compact Sports Series and eventually can have access to 102 cars (118 cars after purchase of the downloadable content). Most cars can be bought in exchange for kudos tokens, although some can only be obtained by completing enough races at a high level. Each car is made from around 10,000 polygons.
In arcade racing there are 60 medals available, 20 each for street racing, timed runs and cone challenges. Each race is with a preset car and track.
Time attack does not use kudos, the aim is for the player to try to get round the circuits as fast as possible. The player can either choose circuit or car challenges. In circuit challenge the player can choose from a selection of up to 92 circuits and then choose any car to race in. In car challenge the player can choose from a selection of up to 102 cars and race on a predetermined circuit. In both styles circuits and cars may only be chosen if they have previously been unlocked in kudos world series or arcade racing. If the player enters the showroom, it can view and test drive all cars on a test track. The players can also race against a ghost car that got the record time.
Challenges are divided into five difficulties: Steel (novice), Bronze (easy), Silver (medium), Gold (hard), and Platinum (expert).
Online
Unlike many other Xbox Live enabled games, Project Gotham Racing 2's online ranking system is solely based on the kudos earned online. One can not go down in rank, only up. In this way, one's rank does not necessarily reflect their skill.
Geometry Wars
Within the player's car garage, an arcade cabinet can be interacted with to play Geometry Wars, a top-down multidirectional shooter. This marked the first appearance to the public of what would become an entire series of similar games.