In this paper, the impact of network induced timedelay on Networked Control System (NCS) and the weights of Sensor-Controller time-delay and Controller-Actuator time-delay is analyzed by simulations. Furthermore, the effects of plant parameters on stability region of PID controllers in first-order and second-order systems with time-delay is also studied. Finally, an open-loop zero was inserted into the plant-unstable second-order system with time-delay so that the stability region of PID controller gets effectively enlarged.