I did the food for our DD christening, also had around 60 people back at our house.
It wasn't that much trouble to be honest, although I do love to do these things normally.
I did a buffet and had the following.
Cold Salmon steaks cut up (cooked in foil with a little olive oil and some fennel)
Cold Ham Joint sliced
Mini Beef and Yorshire puddings link here, they went down really well
Mini Chicken Pies (can't find recipe but had peas and creme frais in)
Samosas (friend made)
Cous Couse
Greek Salad
Summery Potato Salad
Roasted Tomatoes
Baguette
Then puddings, such as triffle, and christening cake.
I did all the work beforehand, and even laid it all out on the table covered in foil before going to the church, so only had to remove foil when I came home, that way I could join in with the chat etc.
All the children played in the garden and over the road in the field so I didn't have to worry about games etc, but I did buy one of these for each child to use during the service