Having made an all-seasons, multi-character Buffyverse vid, I can offer this: Do not start ripping/capturing until you have a detailed roadmap (in your head or on paper/pixels) of what you want, with as many specific clips identified as possible. If this means re-watching a whole bunch of eps, so be it. Trust me, you don't want to do what I did and wind up with 60 GB of clips and no idea where to put any of them. The ripping time alone! It is to make you scream.