How to change Firefox file opening defaults?

[Josef Lowder]

.
== Steven Crandell wrote: 
> I've had problems on several boxes where it fails 
> to remember or silently overwrites my settings. 
> Your settings probably live here: 
> /home/username/.mozilla/firefox/somerandomchars/mimeTypes.rdf 
> When I have had a problem with this, I blow this file away 
> and let it firefox rewrite it with my new prefs.

I looked at this "mimeTypes.rdf" file, but didn't 
see where or how I might fix anything there. 

== Dennis wrote: 
> File associations are handled by the Desktop (KDE or GNOME or Widows).
> In KDE look under KDE Control Center/KDE Components. 
> You can change file associations there.

Thanks Dennis.  I was not familiar with anything called the 
"KDE Control Center" and had a bit of a time finding it, 
but finally stumbled around and found it and eventually 
figured out how to make the changes I wanted.  All good now. 

K > System > Configuration > KDE > Components > File Associations > 
   (Found "Filename pattern") pdf > application > pdf 
   (under "Application Preference Order" moved xpdf up [Apply]

Apparently doing that set 'xpdf' as the default. 
Did the same thing to set .jpg files to open with 'kview' 
as the default.  So I'm all set up now.