What game should i get for my birthday?

Buy The Orange Box. It is a couple years old now, but has some of the best games ever on it. You will get Half-Life 2 (Rated the 5th best game of all-time by gameinformer), along with the two expansions to it. You will also get Portal which was selected game of the year by certain developers. You will also get Team Fortress 2, an online game that is a mod of Half-Life 2. If you are looking for a newer game is suggest Portal 2, it is an amazing puzzle-based game you can play on your own or with a friend.