[CentOS] how to create an mpeg4 mimetype (OT)

Hi All,

I think this may be off topic, but since it's through centos 5.2, I'm 
not sure.

Here is what I would like to do:

I have created a web page for family to log into and view clips of my 
new niece.  My camera saves these clips in mpeg4 format.  What I would 
like to do is have the web clients click on the link and have either the 
clip pop up a save dialog or even better, start playing the clip.  Right 
now if the link is clicked it starts downloading right away but the file 
looks like gibberish. I guess what I am seeing is the raw code.

I think it's a mimetype thing but I'm not sure and if it is, how would I 
create the mimetype entry to do what I would like?

Thanks in advance for any and all information received.

Phil