I found an old movie,  I started downloading last night and there were only about 10 peers.  Even so it was coming in fine.  When it got to 87%, it didn't stop, but almost.  I left my computer running all night and it is still showing incoming bits, but so slow i'm still at 87%.  I just tried to download the most popular movie and it too is very slow.  Is my cable provider blocking torrent traffic?

It's not a client-related issue, that much is certain. Doesn't that torrent has a comments section, or the site you're getting it from, a forum ? It would be a more logical place to ask about.

Likely, the torrent you're downloading is still only being seeded by a small number of people (perhaps even just the original uploader), and everyone else is at 87% just like you. Or the swarm simply slowed down because some of the few seeders withdrew, or slowed down. Those would be the most common situations.

Of course, it's assumable that by now you've already long since finished it, or that it died for whatever reason (it happens).