I would have to say that my top PS3 games are:
Uncharted 1-3: It is a action-adventure game. You play Nathan Drake who is suppose to be a descendant of Francis Drake, who seeks out lost treasures like El Dorado, Shangri-La and the lost city of Iram of the Pillars. As Drake you jump, climb, sprint, swim, scale narrow edges and wall-faces. It's one of my favorite games.
The Last of Us: Third-person survival horror action game. It is set in a post-apocalyptic US that tells the story of Joel and Ellie. Throughout the game Joel and Ellie work together on a westward journey across the US to find a possible cure for the plague that has wiped out the human race. By far one of the best, if not THE best game I have ever played.
Heavy Rain: This game is more of an interactive movie than it is a video game. It is a psychological thriller, where you play 4 different character in the search for the Origami Killer. Ethan Mars, the father of the kidnapped son of the Origami Killer, Madison Page, a journalist, Norman Jayden, an FBI agent and Scott Shelby, a private eye. All different characters that do not know each other but are all connected.
I would suggest playing anyone of those games!