I am trying to start my game but its glitching out!

[Montgomery]

When i start my game it loads normally except when i am supposed to be in game, if its the loading part of the guid, i am still in my dekstop, i hace the arma 2 mouse icon and can click buttons but am still on my desktop, it works in windowed mode but when i change it from windowed mode into full screen the bug continue to break my game! help please!!!!!