Does Google Analytics only count a Unique Visitor if he/she lands on the index (home) page? What if the UV makes his way to a side-page of your site but never visits the home page (index page)? Would he still count as a unique visitor under Google analytics?
No if a visitor lands on any page of your website and has not visited the site within 30 minutes they are considered a unique visitor. It doesn't matter which page they go to as long as you have Google Analytics tracking code installed.