Check out Positive, Comparative, Superlative by rogersgeorge. Here is an excerpt:
The rule is that when you compare two things, you use the comparative form (see the Andertoons comic below), and when you select from three or more, it’s called the superlative form.
The kid in the comic has a point. When the word you want has three or more syllables, use more and most with…
The full article is available here.
