Order you should play a game series.

[Prelauncher]

I also recommend playing the games in the order they're released for the reason kreekakon said but also for gameplayreasons; The game that were released first usually have the least mechanics and the least improvements. As a series of games are released the developers will have more experience, better tech and a whole lot of consumer feedback making each installment with better gameplay than the previous. Obviousley this is not always the case but it is often enough.