Internet Iexplorer

All my browsers will open in a new window?
Hi everyone I wonder if you can help me. all my browsers internet are somehow corrupt. when I open a link in some way opens in a new window. my IExplorer, Netscape Navigator, Safari, Opera all open in a new window and is very irritating. Please Help !!!!!!!!
Tools, Internet Options, tab (Settings) open links in other programs – check the "current tab or window" in this box is Explorer 7
New Security Features in Internet Explorer 7