Are book clubs fun??????????

It all depends on who's in the club with you, and what you're choosing to read. The frequency of your meetings should be based on what you choose to read, to make sure everyone has time to read what you're choosing. 5 or 6 is a good number - that way you can have good discussions with multiple opinions. The library is a good place, but you should go there and ask if they have a room where you could meet and not bother anyone else.