Log in fails after installing additional drivers

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http://askubuntu.com – So I updated my graphic drivers using the additional drivers option and restarted my computer upon completion. Now when I try to log in everything looks fine, I put in my password and hit enter, what comes up next is the screen with one(1) distorted icon on the desktop, and the background, nothing more. How can I revert back to the default graphic drivers so I can boot into Ubuntu again? Let me know if you need anymore details. (HowTos)