To make a quirky picture frame try varnishing favourite sweets, jelly babies or licorice, all sorts look quite colourful, then glue them to a cheap picture frame. I suppose you could do the same by varnishing cookies, but make sure who-ever you're giving it to knows it's not really edible!
One year, for Christmas, I made a collosal gingerbread house using every kind of candy I could lay my hands on. Once finished, I decided to seal it so I could use it as a decoration year after year. After making sure that the gingerbread had fully dried, I coatd the house with a sealant. Great thought, but in reality it did not work. Where I live, it is HOT and humid in the summer. Even though we have air conditioning and I kept the house in a cool place, after a couple of years, the candy got soft (like old 'hard' candy does). The house was ruined and had to be thrown out. We'd have gotten more pleasure from allowing the little ones to eat it. I'm sure if I'd lived in a different area, the house would have 'kept' better. My point is, take your climate (and the type of candy) into consideration before attempting to preserve sweets like this.