Go to
Nikon USA and look for firmware downloads.
I copy the firmware to a camera card directly from my laptop, but you can do it from any camera card reader.
You will have to follow the instructions very carefully as you have to download both A and B firmware. The version for the D200 is 2.00
Follow the instructions and make sure when you are done you go the the menu that has the firmware in the camera and insure you have A. 2.00 B. 2.00
Basically firmware makes your camera perform properly. Newer versions of firmware improve operability.
Please take the time to read the manual. It will help you understand camera actions and functions. Besides, you will get so much more out of your camera.