On the graphics panel you can adjust the battle graphics quality (according to the capacity of your PC), pick from a range of screen resolutions and select advanced options such as anti-aliasing, shadows, water effects, and brightness and gamma correction.
The sound panel enables you to change the volume of speech, sound effects and music as well as some advanced options such as the number of channels and memory used.
Listed on the controls panel there are a wealth of keyboard shortcuts that can be used instead of mouse actions. There are also options to adjust the in-game camera settings.
The user interface panel enables you to adjust various aspects of the battle interface and whether unit/ship flags, banners and markers appear when in battle.
Brightness & Gamma
The brightness and gamma correction can be adjusted here; simply move the sliders and watch the effects change dynamically, then click on the "tick" button when you are happy with the balance. Use the button on the left-hand side to return to the default settings.