Say you want to disable the automounting feature of Ubuntu. You can press Alt+F2 and type polkit-gnome-authorization. Press Enter and in the new window that appears go to Storage > Mount file systems from removable drivers.
Press Edit.
Select Active Console: Authentication.
Press the Modify button.
Alternatively, if you only want to disable the Nautilus window that opens up every time you plug in a storage device, the simpler method for this is to open up Nautilus, go to Edit > Preferences > Media and turn off Browse media when inserted.
polkit didnt work for me. None of the options you mention are shown in mine. However I found the following to work.
In a terminal run
gconf-editorBrowse to /apps/nautilus/preferences and you will find two keys: media_automount and media_automount_open.
media_automount controls whether to automatically mount media. If set to true, the Nautilus will automatically mound media such as user-visible hard disks and removable media on start-up and media insertion.
media_automount_open controls whether to automatically open a folder for automounted media. If set to true, then Nautilus will automatically open a folder when media is automounted. This only applies to media where no known x-content/* type was detected; for media where a known x-content type is detected, the user configurable action will be taken instead.
This user configurable action for specific media types can be configured in the Nautilus window. From the Edit menu in Nautilus select Preferences and then select the Media tab.
I have updated https://help.ubuntu.com/community/Mount/USB to reflect these changes in Ubuntu 9.10 Karmic Koala.