Which browser are you using?
If Firefox then: Click on Tools > Add-ons > Extensions, and look for WOT and the buttons at the side of it. Either Disable it or Remove.
You can uninstall WOT for Internet Explorer from the Windows Control Panel option Programs and Features just like any other Windows program. Remember to close all Internet Explorer windows before uninstalling.
If it's any of the others, go to ClickHere and then click on the Browser you are using and mostly uninstall is the last FAQ in the list.