Try download a 30-day freeware call ZDelete at http://www.zdelete.com to see if it can help you to remove that stuborn history.
I can't clear certain sites out of my internet history for some reason. And they're just random sites I've visited (ie: A certain news story in a pittsburgh newspaper or a certain item i looked at on a store's website). The sites are all about a year old and they keep autocompleting in my address bar, even after I clear the history. I did a windows search for any documents either named or containing the web addresses and it haven't found anything yet (and i did include search system files and subfolders and hidden folders)... any ideas?