Playing style

Winning matters not the style. Depending on the given position, I don't mind being aggressive or defensive.

Positional Prophalaxis!!! Karpov+Petrosian FTW!!!!

I'd have to go with positional as well. As Elona so eloquently put, control the board, control the game. If in my steadily gaining more & more territory my opponent slips up & makes an exploitable weakness then I'm on it like a duck on a junebug. But really it varies from game to game. If my opponent wants to forgo the development stage & comes at me with just a queen & bishop, then I say bring it, and I do what I can to shut him down quickly. or if I think they are playing too passively, then I will try & take charge and see what kind of attack I can get going. Ultimately, I would say I just try to play the board.

I'm surprised by the amount of 1500- positional players 
I don't think players at this level has the necessary knowledge to appreciate and turn small advantages into a won game. Furthermore games are decided by tactics 99%.