Usually when refering to cooking books/recipes, they tell you what temperature to preheat your oven to, but never say if you should use top heat/bottom heat or both. My question is when do you know which setting to use?
In general, if you have heating elements on the top and the bottom, the top one is for broiling. So, if the recipes calls for broiling, that's when you use top heat. If it doesn't specify that, you can assume it's a baking-roasting type dish, and use the bottom heat. In either case, don't forget to pre-heat the oven to the desired temperature.