Typically it is easier for the beginner to start with a Freshwater tank. Fish are usually less expensive than saltwater and are more forgiving to fluctuations in water properties. Additionally Freshwater fish owners are easier to find for assistance (even though all advice is not always correct) Regardless of what you choose read as much as you can about them before you buy. Always be prepared to ask for help because it is not just your pride but your new aquatic friend's life.