I would also recommend using private torrent sites to get your torrents (Don't ask for site names you will not get an answer find them yourself) and running Peer Guardian 2 which makes it safer to download through p2p.
i just started using utorrent, and all my downloads seem faster... i think its cause of the config for the prog..... along with what gg said above... :D
There are two trackers that I go to that have Azureus banned because it is to easy and there are so many cheat scripts out there that people try to use to cheat. So instead of always adding anti-cheat scripts to the site to catch and ban them they just baned Azureus all together.
Plus as stated above it can be a resource hog and slow your computer and torrent speeds down.
uTorrent is the client I use because as far as I know every tracker that I have ever used has always allowed that client.