Program to take screenshots while in-game (DirectX, Call of Duty 4)

I'd like a program that a user would login on (I will supply database information), and the program would minimize to the tray. The program would take random in-game screenshots and upload them to my server. Obviously the screenshots would have to be compressed so the program would not take up a large portion of the users' bandwidth. The program would need to only take screenshots while Call of Duty 4: Modern Warfare is running, otherwise it will display a "paused" icon in the tray. I will supply the normal icon and paused icon. The overall goal is to allow players on my server to become "verified" by using this program. It will establish a level of trust not typically found by showing in-game screenshots while this person is playing. It must work while anti-aliasing is enabled in the client's game. It would be a plus if a message could be shown in-game at the top of the screen. I will supply the message if you are capable of doing that. The program will need to allow me to change the database user/password that it checks against for username/password verification from time to time.