Are you taking about the options menus when you start the game (where you can choose number of zombies, air drops, etc?) or options in the game launcher (use EAC, or the game options flags too can manually set) or the game options when you open the command console?
I initially thought you were referring to the first one (which might be in moddable XML files) but the more I think about it there are several places for game options/menus.