not only spiked humor then? any qt video?
like...
http://www.apple.com/trailers/fox/tl...er/medium.html
or...
http://www.apple.com/trailers/paramo...ii/medium.html
none of them play?
do you have any .mov files you can play in quicktime off your pc? and if they play, try rightclicking the fire, open with... and choose quicktime and check the box that says always use this program. not sure what diff that would make on a webpage file tho.
Also, in your firefox folder (where its actually installed) in the plugins folder there, it should have a bunch of npqtplugin files, and a quicktimeplugin.class File.
And Finally, What Firefox version do you have? (goto help, about firefox, and it says the version)