Since you're not sure when the Christmas dinner will occur, I'd say freeze. The candies **should** freeze--I know from experience that peanut butter balls (or whatever they're called in your neck of the woods), all types of cookies (including the ones with the kiss on the top and iced sugar cookies), peanut clusters, pretzel rods/chocolate dipped pretzels, and Oreo cookie balls all freeze well.
As far as the kiss-cookies-in-the-tin question, at our house we make them with chocolate stars, but I assume it's a similar principle. If you don't want them smushed, I'd give them at least four-five hours to cool and set enough to stack (maybe more). Or, we let them cool in a cooler part of the house, such as the basement or the garage, since it seems like cookies just don't cool as well or as quickly in a hot kitchen, especially with the oven on and lots of baking and cooking going on.