And press OK button
If it ask you press Continue in Safe Mode
Test Google searches now and let me know results.
If you don't experience any problems in safe-mode then you must check your add-ons in Firefox.
Open Firefox and from Tools menu select Add-ons
Disable them all and restart your Firefox
If you don't experience any problems then go to Add-ons and enable first add-on then restart Firefox
If problems starts then this is the bad one
If problems don't start then enable another one and so on until you find bad one
When you find it remove it from Add-ons.
Let me know results.