Here is an example of how to disable and enable individual shortcut-keys in Compiz:
Assign these two commands to hotkeys, or just run them in the terminal (either asis, or in scripts).
You can setup your shortcut-keys via "Keyboard Shortcuts" in the Preferences Menu... (I use xbindkeys.. It has finer control over wihch keys you can use. eg Numlock on/off makes a difference.)
Turn enable the shortcut-key for: Zoom Specific Level 1:
gconftool-2 --set /apps/compiz/plugins/ezoom/allscreens/options/zoom_specific_1_key --type string "<Shift><Control>Return"
Turn disable the shortcut-key for: Zoom Specific Level 1:
gconftool-2 --set /apps/compiz/plugins/ezoom/allscreens/options/zoom_specific_1_key --type string "Disabled"
If there are many hotkeys, just make two scripts: one for on, and the other for off
You can find all the Compiz keys in Gconf Editor: `gconf-editorenter code here