I've hardly ever used a bittorrent client. Last time I did in Windows something strange happened, the file I downloaded was legit and above board, but suddenly in my yahoo sent mail folder were spam emails that I had obviously not sent... This time, I'm running Linux in a virtual machine using KTorrent, should be a bit safer
i'm assuming ktorrent is a copy of utorrent, in which case, you may be able to set schedules in it..
ie, during the day, limit the download/upload speeds