No the game is not a dos game, and i dunno why it could give him an error like that, but again, the game is full of bugs as i play it and i have problems with it constantly.
Its a great game man, but want my suggestion? return the game, and buy X2-The Threat or The new space simulation called something jupitor incident
I believe u r into space simulations so u can go to the store u bought IW2 from and ask him for suggestions but i persoanlly like X2, and space rangers.
The problem ur having might not even be a faulty thing in UR pc, it could be the game itself