ok, thats the link to adobe AFTER EFFECTS.
thats just pretty much the badass FX like fades, wipes, and shit you can throw in AFTER you edit the video. seeding means that after you finish downloading, you upload it to the other people who are trying to get it.
its not illegal to download it. what is probably illegal is installing it using the activation key that they provide. you also need a bittorrent client to download the file.
ABC is a nice one: http://pingpong-abc.sourceforge.net/
but pretty much you'll be safe to use this site. i've used it for awhile and gotten oodles of music, movies, programs, and just about whatever i use on the computer from it. you don't download from a server, you actually download it from everyone else who has it and is on the site pretty much. thats the best way i can describe it.
like, one person uploads the file to another person, and then the next person has 2 people to download from, and then the next person has 3 sources, and the next has 4... etc.....
hopefully that makes sense