No, disconnecting the battery will not reset the anti-theft system. The anti-theft system is designed to keep your car from being stolen, and it does this by immobilizing the engine. Disconnecting the battery will not reset the anti-theft system, and in fact, may make it harder to reset if you don't know how to do it properly. If you want to reset your anti-theft system, you'll need to find the right procedure for your specific vehicle.