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Hi Mike, First off, if you have a couple hours to spare, I'd start by watching a couple of videos. They are over a year old, but still contain tons of good knowledge about using Moz tools http://www.seomoz.org/dp/pro-webinar-november-2010-with-danny-dover http://www.seomoz.org/dp/webinar-february-seomoz-pro-overview Yes, fixing errors is often considered "low-hanging-fruit" and can sometimes have a quick effect on improving your rankings - but not always, unfortunately. For beginners, the On-page optimization tool is one of my favorites, because it contains so much knowlegde in a single tool. Pick a keyword, URL, and get to work. Hope this helps! Best of luck with your SEO.