Firefox / Windows Media Player problem

Still no luck in getting this to work - viewing a "wmv" file in my Firefox browser. I think I know where to look - but can't figure out HOW to make the fix. ----- when I go to TOOLS --> OPTIONS --> DOWNLOADS it doesn't look quite the same as it does here (download options) on this FIREFOX page. I have nothing, NADA, in the box for FILE TYPES, and the CHANGE ACTION and REMOVE buttons are inoperable. I can click PLUGINS, and get a long list, WHICH DOES NOT INCLUDE WMV files, and I can not take any action on the follow-up page (when I click PLUGINS)

So far I got 3 guys emailing saying it works fine for them, and one guy seems to have the same problem as me, he can't view the movie clip in the browser, so he downloads the file. ANY SUGGESTIONS?