If you have to lock your wheels in order to stop, you are doing it wrong. Take a curling rock, and throw it down a sheet of ice. It will slide. That's what locking your wheels does. All you can do is slide. You will not lose momentum, which you need to do in order to stop. Worse, because your wheels are locked, you can not steer.
On snow and ice, you want your wheels to keep rolling. Remember that curling rock that I told you a minute ago to throw down a sheet of ice? Now take something that will roll. You'll find that the object that can roll will not go as far as the curling rock. It's physics.
Driving a vehicle with ABS is a whole different animal from driving one without. Without ABS, you press the brake pedal until you feel a wheel lock, then release it until that wheel starts rolling again. Wash, rinse, repeat. With ABS, you press the brake pedal as hard as you can, and hold it steady. Don't worry about the fact that it's making nasty noises, and you feel the pedal pulsing under your foot. That's the ABS system doing it's job, pumping the brakes faster than you can with your foot.