i tried to download a file yesterday, it started the bittorrent download tracker but the progress stays at 0.0% for over an hour!
1. It's always better to use powerful client such as bitcomet or bitlord, or
shareaza 
2. Go here to check if your bittorrent port is open:
http://jlh.no-ip.org/connectiontest/If you get a TCP connection error, that means you have to reconfigure your firewall or router.
3. Make sure that your torrent link is still valid (find out at the tracker's website).
4. Begin your torrent, then look at the stats.

Choked = The user is busy uploading to other users. Your turn will come eventually, but how long depends on your fair share.
Uninterested = The user doesn't currently have parts of the file you need.
Downloading, but 0.08kbps mostly = You/They have used most of your/their bandwidth.