For bit torrents I've tried various different clients, and Azureus
is by far the best I've found. Unfortunately it needs java 1.4 or better and so used to be a bit slow, but the latest version is quite fast. It can be made to scan a directory periodically for new torrents, so there is no need for "helper apps", just always save new torrents to the same place. I can't recommend it enough.
The junk you get after clicking on a .torrent is the browser showing you the data inside the torrent file. You need to right-click on the file link and select "Save Link to Disc...", because the browser is not recognising that you want to download the file, not look at it. With a bit of digging you should be able to configure the browser to do this automatically.