small internet explorer problem

whenever im on google searching stuff (duh), a new window is opened when i click on a search result. ive never seen this before and im not too sure how to fix it. im using vista home basic

 

there's also an option in google's preferences to open a new window, you can uncheck the box.

 

i checked my google preferences and the box was unchecked. My tabs havent been touched either. i think im in need of a good, hard clean.