Title Case

I was just reading a wiki article, and to my disappointment, the answer to a question I've been wondering about for a while (how do you properly case titles?) has no definite answer.
But it kinda put me in the mood for a pointless poll :D
So, how do you generally case titles?

#3 myself. No real reason, just do (seems the most natural to me).


The Vitamins Are In My Fresh California Raisins
"Start case" — capitalization of all words, regardless of the part of speech

The Vitamins Are in My Fresh California Raisins
Capitalization of all words, except for articles, prepositions, and conjunctions

The Vitamins are in My Fresh California Raisins
Capitalization of all words, except for articles, prepositions, conjunctions, and forms of to be

The Vitamins are in my Fresh California Raisins
Capitalization of all words, except for closed-class words

The Vitamins are in my fresh California Raisins
Capitalization of all nouns

The vitamins are in my fresh California raisins
Sentence case – Capitalization of only the first word, proper nouns and as dictated by other specific English rules

#1 makes me want to cry, #6 is just a normal sentence, and #5 is just a normal sentence in German. As for the others, I think I was taught something along the lines of no words less than 5 letters long, unless it's the first word of the title. But that's probably because they don't really teach grammar here, and nobody knew what prepositions or conjunctions were, and 5 letter words sounded like a good rule of thumb. Heck, I still don't know what closed-class words are. By the "less than 5 letter" rule, I should pick #4, but that looks wrong to me, so I'm saying #3.

EDIT: Maybe the 5 letter rule was that we were supposed to capitalize prepositions longer than 5 letters, like throughout...3rd grade was a long time ago.