Title = your headline. Keep it short and sweet, preferably with the name of your community, and in Upper/lowercase, please. (NO NEED TO WRITE REALLY REALLY LONG HEADLINES IN ALL CAPS!!)
Tagline = a few words or a phrase that can identify and distinguish the story for future reference (e.g., a State Fair story could have a headline without the words "state fair" in it, but if you put them in the tagline, the story would come up in a sitewide search.)
Stories could be three sentences long or 30, but they have a beginning, a middle and an end. The most effective stories follow this formula: 5Ws + 1H.
(Translation: Who, What, When, Where, Why and How; answer as many of these as possible and you've got a definite story on your hands.)