This should help you remove the error: http://malwaretips.com/blogs/backgroundcontainer-dll-virus-removal/
Should you still wish to remove IE11, you do it by "rolling back" to the previous version you had, which happens automatically when you uninstall IE11:
Control Panel > Programs & Features
Click "View Installed Updates"
Scroll down to Windows Internet Explorer 11
Right-click on it and choose "Uninstall".