Some years ago I’ve been involved into pop-up windows blocker development (module to prevent undesired browser windows to be opened). In case of Internet Explorer the most usable approach is creating Browser Helper Object http://en.wikipedia.org/wiki/Browser_Helper_Object
According MSDN:
IWebBrowser2 Interface
Exposes methods that are implemented by the WebBrowser control (Microsoft ActiveX control) or implemented by an instance of the InternetExplorer application (OLE Automation).
So unless application uses ActiveX, you just get the instance of IE started, which loads BHO, which may prevent the page from being opened…