If your refrigerator is more than twenty years old, you probably spend more on electricity in a year than the price of a new Energy Star appliance. You should replace it for that reason alone.
Ice cream freezes at 26F and quality has nothing to do with it. "Quality" usually means more than the usual amount of sugar. Yes, it's true: you can use up to 20% sugar to make ice cream and people will swear it's creamier and higher quality than a batch using less sugar.