Snorlax is a good pokemon. Though its speed is very slow, its attack and special defense is quite high. I highly recommend you have one in your team. Give it hyper beam,ice punch,counter and return. It learns hyper beam at level 53. It can learn attacks like block, rollout and body slam. Body slam would be my second choice. It paralyzes your opponent, thus giving snorlax the advantage to strike first. If you are the consious type,make sure it is timid nature and let it hold leftovers.

PS: Beware of its speed--its very slow.....