a Torrent is basically a file that then pulls bits from people called "Seeders" who host the file on their computer. With enough seeders and a constant connection, download times are fast.
Use a program as simple as Bittorrent to open the .torrent file. It will then download the torrent and unpack the contents of whatever it is (a folder, zip, exe, etc)
From there you are done... but be nice and seed for a while till your share ratio is well above 80% or you do not see any uploaders.
There are many torrent search sites out there but i found i can locate pretty much anything by typing what i want in google followed by the word 'Torrent'