You have adware my dear friend. That's what's causing you to be redirected to different sites. Try getting rid of the shit toolbars that you don't use, clear your temporary files, and run a spyware/adware removal tool. I suggest Spybot Search & Destroy since its one of the best ones out.

And I also think you are better off running Firefox. Its a lot more secure, they had add-ons that will let you customize the crap out of it, and have Ad Block + which will clear all advertisements from websites. When you install Firefox, you can transfer all your bookmarks and cookies and such from IE8.