bittorrent !!a very good client is utorrent just google for the torrentsites e.g www.isohunt.com is helpful too
Probably your router is bocking a necessary port. Might also need to change to different ports as some ISP's reportedly block common sharing ports. Try UPnP, if your router supports it. It supposed to do that port management for you.There are some good wiki guides out there to do your config. Google.But, what do I know - I is only a pianizt.