Thank you very much!Salaam. If you are using Firefox then i would highly recommend "AdblockPlus" and "Noscript" (If you are still using IE i urge you to ditch it for Mozilla Firefox)
There are many other add ons which are beneficial but these two are one of the best around.
Links: Noscript - https://addons.mozilla.org/en-US/firefox/addon/722
Adblockplus - https://addons.mozilla.org/en-US/firefox/addon/1865