Oprah is most definitely a formidable opponent when it comes to anything and believe it or not she influences you everyday life. Being the all powerful overlord that she is there are ways to defeat her or at least defend yourself, these methods haven't been proved but could work. First off if Oprah is able to send her robot menace to attack you your one defense is Teflon. Robots cannot cling to Teflon no matter what the circumstances, so if you can climb a Teflon pole or line something with plumbing tape you'll be able to fend off her robotic minions. Next if Oprah is using thermal vision your best bet would be to go behind a large building or toward a flock of people, this would throw off her sight. To defend yourself against her mind control you need to either refrain from looking her into the eyes or wrap your head in some sort of metal such as tinfoil or possibly a metal lined hard hat, this should somewhat protect your mind. Another way to stop her mind control would be to disrupt it by adding another wavelength to the equation changing the message being transfered. To block out her control either go towards a radio tower or expose her to other wavelengths such as X-rays or microwaves. Lastly her acid breath would be the toughest thing to defend yourself against, you'd have to freeze it before it reached you or put a barrier between you and the acid. Seeing as her breath is most likely a pH of 12 you'd need either a solid concrete wall or some liquid nitrogen to stop her from disintegrating you. In conclusion Oprah is in fact one of the toughest modern day villains to defeat. To find out about protection on a global scale, once she's reached Mars, read the section Global Defenses.