I'm a Big Furled Leader Formula fan...as aged_sage mentioned . You can plug in the length you want and the number of strands you want and the number of stepdowns [that is the porportion John mentioned] and it will give what some of us consider the most efficient transfer of energy.
Having said that IMHO furled leaders are so efficient that it probably doesn't matter very much.

The short answer to your question..."I don't think I can just use the board I made from Kathy's dvd and change it length and peg positions or can I?"...is yes you can. That's what I did at first ...I just added more pegs to the board and marked them relative to the particular leader I was after. Of course when you do enter the dark side you will want to make a board on which you can vary the positions of the pegs rapidly and easily.

I prefer using pegboard...others have more of a channel to slide the pegs in.

I think that what boards the folks use and their reasons should be the subject of a separate thread ,now that we have a "Furling" forum,....there are many good ideas out there.