Is there a way to protect the add-ons?
Some add-ons come with an optional use of a password to protect them from unwanted modifications, but this is completely pointless as the password does not protect them from being easily and quickly disabled or even removed.
I am hoping for more password protection, rather than some code that could also be easily removed.
Alla svar (3)
you could try the public-fox addon:
Any extension can easily be bypassed by starting Firefox in Save mode.
- Help > Restart with Add-ons Disabled
for locking certain settings in about:config you can also refer to http://kb.mozillazine.org/Locking_preferences - however it is also far from bulletproof when the user has access to the filesystem.