Remove and Disable Yahoo! Search from Firefox
One of the neat tricks with Firefox is that when you type in a partial URL into the search field, say for example "netflix," Firefox will automatically direct you to "http://www.netflix.com/."
This is very useful because you do not have to type in "www" or ".com" or anything else.
Firefox does this trick by using Google's "I'm Feeling Lucky" feature. So, while you never see Google.com, you are actually using the Google search engine to find the partial Web address that you have entered.
This all works great unless you somehow download the Yahoo add-on which makes Yahoo! Search the default browser for Firefox. If you have AT&T DSL service or if you installed Yahoo IM (Instant Messenger), you may have installed this Yahoo add-on without being aware. Yahoo does not alert you that this add-on is being installed to Firefox.
If you have the Yahoo add-on in Firefox and you type a partial Web address into the Firefox search field, you will not go straight to the Web site. Instead you will see a list of Yahoo Search results.
This is a step backward in terms of usability, but it is also very easy to remove/disable this Yahoo add-on feature from Firefox. To make Google your default search engine in Firefox, just follow these five easy steps:
Step 1: Open a new Firefox browser window.
Step 2: Type about:config in the search field and press Enter.
Step 3: Click the "I Will Be Careful" button if necessary.
Step 4: Scroll to find a configuration key titled: keyword.URL
Step 5: Select "keyword.URL" and right-click, then hit "Reset" from the drop-down menu.
Firefox will automatically reset the URL value to http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=navclient&gfns=1&q=
This should solve your problem and remove/disable Yahoo Search from Firefox and go back to Google.