Anti-lock brake systems, or ABS, are designed to allow a driver to maintain steering control of an automobile while providing near maximum braking effort. ABS brakes feel different that "normal" brakes when used properly, and most driver's aren't accustomed to the pedal feedback provided by ABS.
To properly apply the brakes in an ABS equipped car during a panic stop, simply step on the brake pedal with as much force as you can. You will feel the ABS pulse back through the brake pedal, but this is a normal part of their operation. Likewise, you may hear noises not familiar to you in normal vehicle operation. Continue to brake with maximum pressure as you steer to avoid whatever is in your path. Never pump the brake pedal on an ABS equipped vehicle, as you will defeat the ABS function and lose vacuum assist to the brakes, which will reduce your cars braking ability.
It's a good idea to familiarize yourself with your cars ABS, so try a few panic stops on a dirt or gravel road to get used to the system's operation.