Quick, easy, but good food to serve at a party would be pizza bagles, rolled ham and cheese, sloppy joe, hot dogs in buns wrapped in colorful napkins like their wearing a party dress.
It depends on the type of party you want to have and whose birthday it is. Finger foods are nice because they recquire less immediate prep than fancier foods. They also allow guests to mingle and walk around. A sit down dinner can have a lot of risks and complications.