Questions about resolution

Hi everyone.
I’m doing the menu for my game, so:
how can i change the resolution?
I read that you can set it with command line launching the player, but i was wandering if it is possible to change it inside the game (in blender 2.53)
If not, it is possible to launch a .bat file inside blender with python?

I haven’t tried this myself, but would it be possible to set keyframes for the resolution, then whenever you click a resolution button it would go to the corresponding frame of the animation?

check my tool for this:

this is a config program that makes .bat