The weather is probably the number one thing that people who do not know each other well discuss. Sports news is a very common topic, especially if a local team or player is in a tournament or play-off or doing extremely well or badly. Entertainment news, such as a celebrity who is in town, is another good topic. Discussing personal information such as salaries or a recent divorce isn’t done between people who don’t know each other well. You should never say something (good or bad) about a person's body. You don’t talk about private issues either.