Well your specs look fine. The only problem I see is your CPU running at 1.6GHz. I had the same issue with my Arma game. The best advice I can give you is upgrade your CPU to at least a 2.6GHz or higher. How new is your Graphics Card? I am not familiar with that certain card. It sounds like it might be quite old, you might have to upgrade that. But I would start with your CPU, in order to run this game you will deff. need a better CPU. A 1.6GHz does not cut it. I had a 1.8GHz and my game was laggier than ever. But I know if you upgrade your CPU you should be off to a very, very good start.

-Wyte