Hello there, Melody! Welcome to planDisney. We are so glad you stopped by!
Goofy's Kitchen at the Disneyland Hotel is one of my favorite character dining opportunities. It's the perfect place to enjoy a meal and some Disney magic on a non-park day or when you want to take a break from the parks. If you booked a standard meal at Goofy's Kitchen, you shouldn't have prepaid. The only time I can think of that may be prepaid, would be special dining events. You do, however, have to include your credit card information during the reservation process. This is to hold your reservation and to charge a no-show fee if you decide not to show up and do not cancel your reservation at least 2 hours in advance.
When you check in for your meal, you can speak to a Cast Member and they will be able to tell you how you will be charged for your meal when they ask how many adults, children, and infants are in the party. The last time I checked children under 2 were free, but you were correct to reserve for four since you will be wanting table space for all four of you.
Melody, make sure you show up with a hungry tummy, and don't forget to try the peanut butter and jelly pizza! It's strangely delicious! Then make sure you visit Mickey's Toontown and visit
Goofy's How-to-Play Yard to burn off some of that yummy food.
Carrie