Step 1: Let's start out with the essentials, shall we?
WOT tells you how safe those sites you visit are. It takes up no room at all. It is a green circle at best, and the more unsafe a site is, the closer it goes to the color red. If a site is code red, it will warn you of this before you enter the site.
Ad Block Plus disables most ads, and if it misses any, all you have to do is right click the ad and select the Ad Block Plus and disable it forever!