I use iTunes or VLC. Check out this thread, there's a link for downloading VLC (it's free & has codecs installed to play most file types, it's very reliable):
http://www.gnutellaforums.com/tips-t...p3-fixers.html
For info about searching & files to avoid etc, see the links that I posted in post #2. There's lots of info there, so just go through it slowly & carefully