How to remove add-ons, fix your home page and search engine by resetting Firefox
The Firefox reset feature will remove the Babylon toolbar from Firefox and reset the preferences it has changed. It will also preserve your personal data but it will restore everything else to their default settings.
1. At the top of the Firefox window, click the Firefox button, go over to the Help sub-menu
and select Troubleshooting Information.
2. Click the Reset Firefox button in the upper-right corner of the Troubleshooting Information page.
3. To continue, click Reset Firefox in the confirmation window that opens.
4. Firefox will close and be reset. When it’s done, a window will list the information that was imported. Click Finish and Firefox will open.
Via Mozilla