Transmission

I'd like to download an HBO series (Six Feet Under) that extended 5 seasons. The total file is 21 GB, but I don't want to wait forever to watch the individual seasons. The torrent is available on my "private" tracker, so I'll need to maintain a ratio. The question is: can I download let's say 5 of ...

Kindly give a quick tutorial on how to manage/reset the ratio counter that appears on the Status Bar. Also wondering what constitutes a "session". Thanks so much for your kind help.
PS: Transmission is the absolute best client out there. I love the minimalism, simplicity, and speed. There's nothing ...