Changing Firefox Browser Settings
To Change the Default Homepage
In top menu bar (press ALT if you do not see the top menu) select Tools->Options
From this screen you can change the default Homepage.
To Change the Default Search Engine
In the search box (to right of address bar), click on the down arrow and select a different search engine. You may remove the extra “Yahoo! Search” entry via manage search engines, which is in the same location.
To Reset Address Bar Searches
Type “about:config” into the Firefox address bar, enter “browser.search.defaultenginename” and right click the relevant setting, then press “Reset”.
To Reset Tab Behavior
Type “about:config” into the Firefox address bar, enter “browser.newtab.url” and right click the relevant setting, then press “Reset”.