This may be splitting hairs at this point, but what really is the difference between burning somebody to death and stoning them to death? Is it just a personal preference, or are you taking something else into account, because I consider them both barbaric forms of punishment.
Barbaric forms of punishment are required for crimes which are of barbaric nature. Simple jail terms, with access to 5-star food and video-game consoles will only encourage these sort of crimes. These people should be made to suffer.