The right church
I know for me since I have 2 children I want to check out the children's programs, see the rooms, meet the teachers, and find out what curriculum they are using.
Worship is another big one for me. What type of worship do they do? I like to see how the congregation is worshiping. Are they entering in?
The messages, are they a good Bible teaching? Easy to follow and understand?
How friendly are people? If I am new I want someone to come to me and introduce themselves.
How active are they in the community? What are they doing to serve or to share the love of Christ?
What about you? What are you looking for when you attend a church?