IE will not allow removal of yahoo

Please somebody tell me how to stop IE ver. 8 from defaulting to yahoo as my home page? I have tried everything. The basic stuff and anti-spyware, trend micro, every other way including fixya, hijack this, etc. This will take more than the usual stuff to remove this mal-ware, etc. Thanks!!

 

Sorry, frustrating, OS is windos xp home,sp3; no yahoo toolbar; no yahoo messenger; ccleaner-free version; no java runtime; tried internet options several times and yahoo keeps coming back up; have startup from control panel and nothing there or in add/remove program that says anything about yahoo. Yahoo is listed under tools as a search engine but not default. Have added MSN as default home page but yahomm comes up first then MSN. I hope that covers it. I have super anti-spyware, free, with tab about keeping home page the home page, does not work. Hope that covers it. Thanks.