From a site? But if it's a site, then why use LimeWire (LW), why not just use your browser? Did you pay that site to access the videos?

Where did you get LW from?

LW is normally sharing p2p = person to person. It's not downloading from any server site, but between people like you & me.
If you mean it's a torrent site, then I've never heard of a torrent site charging people money, unless it was a scam site. Besides, LW is not a good torrent program.

You could try MPlayer. But AVI is like QuickTime .mov format. What audio & video format is incorporated could be anything.