Default applications

[Steve Cayford]

Hello, I'm running a Xubuntu 7.04 (Feisty) system.

When a user right-clicks or double-clicks on a file icon, what controls the
preferred application that gets listed in the context menu? (eg. Open with...)

I know I can change it under the file "properties" and the setting will then
show up in ~/.local/share/applications/defaults.list. However, I would like to
set the initial default so users don't need to mess with this when they first
login. Specifically, double-clicking a text file opens it with emacs by
default, which is a bit technical for my new users.

It seems that this should be controlled by
/etc/xdg/xubuntu/applications/defaults.list, but there is no entry in there
specifying emacs. In fact the entry for text/plain is mousepad.desktop.

Thanks for any suggestions.

-Steve