Building on what LPChip said, since internet explorer is going to be used if it is still available by other programs and scripts, a good way to stop this to simply uninstall it.
Here's how to do it:
Click the Start button Picture of the Start button, type Programs and Features in the search box, then click View installed updates in the left pane. Under Uninstall an update, scroll down to the Microsoft Windows section.
Right-click Windows Internet Explorer 9, click Uninstall, then click Yes when prompted.
Click one of the following: Restart now (to finish the process of uninstalling Internet Explorer 9 and restore the previous version of Internet Explorer). Restart later
http://windows.microsoft.com/en-gb/windows7/how-do-i-install-or-uninstall-internet-explorer-9