Oh I see what your saying, first thing I would recommend is use AutoInject as your
injector and run it before starting Cod4, this will mean that the hack is injected as soon as the game is loaded automatically.
The reason why the hack doesnt run after the game has started is because you NEED to hook into DirectX when it is being initialized in the game so you can run your own code from your functions.
So just set the game to whatever resolution you want and fullscreen/windowed mode then close Cod4 and run AutoInject with your chosen DLL and Iw3sp or Iw3mp(depending on single or multiplayer

) as your game of choice to inject written in the AutoInject.ini file.
Once you set that up all you need every time is to run autoinject and run Cod4 after and the DLL will be injected straight away in whatever resolution you chose

.
Hope that fixes it.
Fleep