Going to a new small group is often uncomfortable. You show up to a stranger's home full of other strangers. It can be quite intimidating, and I think those of us who have led groups for a long time or who have been in the same group for a long time forget that.
I don't know if you've ever noticed, but nothing eases a conversation like food. Stick two people who don't know each other across from each other at a table, and it can be incredibly awkward. Stick two people across from each other at a dinner table, and conversations flow more naturally.
With this in mind, I often begin a new group with nothing more than dinner, introductions, and expectations. We all sit down, begin to eat, and I ask everyone to introduce themselves. After that, I talk about the group's structure, expectations, and any homework or reading we have for the next week.
That's it. There are no other necessary topics of conversation, no other agendas. I just want people to begin to get to know each other and feel comfortable in my home. And dinner is a great way to facilitate that.
If you're starting a new group or feel like your current group just isn't connecting well, try adding the occasional meal to your meeting schedule. It might be the change your group needs.