1. "So, who liked the book and who didn't?"
Beginning the night this way divides the group. Instead, have somebody open up with a question about the title or the point of view of the writer. Soon enough, who liked and didn't like the book will become obvious.
2. "Dealing with the kids/my boss has been crazy—I couldn't get past the first chapter."
Most of us come to book club to escape stress and reality. If somebody didn't have time to finish, that's okay. This isn't high school. It's perfectly acceptable to sit and nibble and listen. Many a beloved member has come, occasionally, just for the cheese and friendship.
3. "This book just makes me so angry! I can't explain why, it just made me so angry."
Emotions are hard. Many of us struggle with what (exactly) we're feeling, which is fine when we're puzzling through a personal decision, but not so fine when it comes to a literary mind meld. The whole discussion will swerve onto what the inexplicably confused person might be feeling, with everybody in the group taking guesses, instead of talking about the book. If someone has a strong reaction, they might want to see if others felt the same way ("Did anyone else find this a difficult read? You did, too? Why so? I'm kind of confused about my own response.") That way, everybody gets a chance to weigh in.
4. "Oh, I would never put up with a man who did [insert gambling, cheating, etc.] and I think it would take a pretty weak woman to stay with him like the main character did."
Ouch. Making judgments about a relationship in a book can too easily translate to real life.