Bittorrent is acting up

Well, this strikes me as odd, because it may very well just be the tracker, or the torrents themselves for that matter. But I've been downloading a few large sized files, and for one of them, it goes to 82% and the upload & download rate just goes to zero, and won't pick up again. not even after leaving it for 4 hours will it move. As for the second one, same thing except 72% and the upload rate goes nuts.

Is anyone else experiencing this? I wouldn't think so, but it might be the torrents...Who knows...