What should we do in Brazil and Chile, South America in February?

My husband and I are going on our fifth “Geek Cruise” for Apple Computer people in February. We’ve taken four before, but they were in Alaska, the Caribbean, and both sides of Mexico. This cruise will be the first to go to South America. We will start in Brazil, go around the tip of South America, and wind up in Chile. On the ship, we will be in computer classes and also in onboard activities. When we dock, we will have planned excursions. However, we are going two days before the cruise and returning home two days after we dock. What should we see and what should we know about those two countries? We are also taking a side trip up to Macchu Picchu after the trip.