1. This will show you how
http://www.gnutellaforums.com/showth...%3E#post163057

2. I don't use WMP but lots of people love it. If you do a search (top right, between faq & home) for video players, you'll probably find heaps of threads about peoples' preferences. VLC seems to be popular & has built in codecs.

3. Some avi are junk, some aren't. There's no definitive answer... lots of junk around these days in different formats. I think you'll find that WMV is the format that people trust the least. Remember, you can check the file out with bitzi before you download. Here's info on Bitzi
http://www.gnutellaforums.com/showth...threadid=37676
Just remember to make sure that the file size looks right for what you're downloading.

4. You can download codecs for your WMP. Here's a link to different codecs & alternative players. If you like, try out a different player & see what you think
http://www.gnutellaforums.com/showth...threadid=40665