For the dipped cones: Put the chocolate chips and white candy melting wafers in 2 separate microwave-safe bowls. Microwave each bowl at 100 percent power in 30-second intervals, stirring well in between each, until the solids are melted.
Place a sheet of parchment paper on a work surface. Put the chopped nuts, mini marshmallows and sprinkles in separate small bowls nearby on the counter. Press the top of a sugar cone into the melted chocolate or candy coating about 1/2 inch deep, then dip into one of the bowls of toppings. Lightly shake off the excess toppings and set the cone dipped-side down on the paper to set. Repeat to dip all the cones.
For the ice cream bar: Set up an ice cream buffet by placing the open tubs of different ice cream flavors in a large metal tub packed with ice. Put the candy-coated chocolate pieces, marshmallows, pretzels, sprinkles, caramel sauce, hot fudge sauce, pineapple topping and fresh fruit into individual lidded pint jars. Arrange the dipped sugar cones face-down on cake stands or pedestals.