Wedding Reception

There are lots of g-rated and Christian themed games avaliable. You can do a version of "The Newlywed Game", where you break people into teams and ask questions like "What is George`s favorite kind of vegetable?". There are lots of trivia games,(including faith based) and they are fairly easy to turn into group activities. There is always charades, and a group game of Pictionary (use an easel, and make your own themes) is really fun. Check out books on shower games, and change the theme to wedding. Shower games are often very tame, and rely mostly on conversations already happening within the group. One of the most popular is one where you hand everyone a common items (beads work well), and as someone mentions a "taboo" word (like groom, bride, or wedding), the one who hears the word collects the beads from the person who says it.
Hope these ideas are useful. You may want to contact the events director at your church for some ideas as well, since that individual often deals with entertaining large groups.
Good Luck, God Bless, and remember to SMILE...the wedding day is often stressful, but remember that people are there to witness your matrimony and share in the blessings and goodwill of the day. Even if you provide punch and chairs for them to sit on, they will find a way to interact and enjoy themselves.