In that case, I logged into a Fedora Core 3 system, choose GNOME as my session and found myself staring a Gnome 2.8 desktop.
I found the file I was curious about, right clicked, and choose properties.
Then I went to the "Open With" tab and choose Xine Multimedia Player and clicked ok.
Now when I right click on it again, I see that
Open with "Xine Multimedia Player"
is the default.
If Xine is not in the list for you, choose Add and it will ask you where your app is located.
You can find it by several methods.
- locate xine (slocate -u will update the database if it's out of date)
- find / | grep "xine" (will work but is slower)
I think you need to be root to do the first, and being root will give you a whole lot less "access denied" errors when doing the last one.
On the FC3 system, xine is located in /usr/bin/xine