Puerto Vallarta, on the Pacific coast, is one of Mexico's top resort destinations.  In town, in the ocean, or in forest, there's plenty to entertain visitors.  Boardwalks in town are worth a stroll to see sculptors and artisans at work.  On the water, active visitors enjoy snorkeling, diving and kayaking, and less active guests can to get on boats to spot whales and dolphins.  Thrill seekers head to the jungle for zip lining and bungee jumping adventures. With something for...