Football for guys is a common one, and popular TV shows, music, and films, but your right they switch quickly from one to another!
I've often found brainstorming before a social occasion helps, think about the people you're likely to see and what they're into, or any news you know about them (i.e. graduations, holidays, passing driving test etc) and note things things on paper (or in your phone) before going out. That way you can get some idea where the conversation might go, and be able to think about how you can best engage with it.