Note that this topic was started in early 2012, more than two years ago, and things have changed a LOT since then. Any discussions of modern adware really has no place on such an antiquated topic, and should be posted elsewhere.
As for a modern solution, if you're having a problem with pop-up ads, randomly-underlined words, hijacked search engines and the like, you probably have some kind of adware. Adware is not difficult to remove, if you know how. It does not require erasing the hard drive. Just go to my Adware Removal Guide and follow the directions there.
(Fair disclosure: The Safe Mac is my site, and contains a Donate button, so I may receive compensation for providing links to The Safe Mac. Donations are not required.)