Do you have the same problem with me after updating your Mozilla Firefox?I just can’t right click after updated into 3.5v new version .Well, if you do have the same problem, you come to the right place.I do have the same problem though, but luckily found the solution.
You will need to check out your existing Add-ons available now in your mozilla browser.Most of the problems that prevents you from right clicking is the Yahoo Toolbar.Disable the Yahoo toolbar add-ons and you can right click inside your browser.In case it doesn’t work, you also have to try one by one add-ons that actually caused it.This should works and there should be no problem for right click anymore.Oh, in case you don’t know, do restart you browser for disable changes to take place.

Thanks..its work..:)