There are many flavors of moron, but in this case I'm guessing you're referring to people who will call down with nothing (and lo and behold, your A-9 suited which made you a huge favorite with a 9-7-2 flop killed you on the river, when he paired his J3o).
DMan's advice is sound, and it really is the key: Wait for their mistakes. However, what you also have to realize (which is sometimes difficult in the example I gave above) is that they are constantly making mistakes. You lost that hand, but you had positive expectation the whole way. You'll lose many hands, but they'll lose more.
I really don't think you should go "slow", depending on what your definition of slow is. Don't smooth call with AA, etc. If you're the favorite, if you think you have the best hand, you have to bet. Your way of making money against these kinds of players is by winning enough money when they don't suck out on you (which most times they won't), so you can afford to pay them the times that they manage to hit their four-outers. If you don't bet when you're ahead, you're costing yourself money in the long run.
But, and this is a big but, you can't take it personal when they manage to hit their draw. You have to be able to lay down your pocket rockets when you realize that they hit a full house with their 63o. If you're the favorite on the turn, however, it's equally important that you jam the pot, and not figure to take the safe route and wait for the river before deciding if you like the card or not. If you're ahead, you bet.