I will advice with Microsoft on this one.
Internet Explorer is basically two components:
1. IE engine
2. IE frontend
You will be amazed to know just how many programs that use that engine and it is indeed tightly integrated into the OS.
Now, if you do not use Internet Explorer, I would block 'iexplore.exe' from internet access (outbound rule) to avoid hard-coded use of the application in various applications and installers.
However, even me who block everything possible have found that blocking the engine is not the way to go (you are better off changing OS to get away from it).
So in other words, you may think you are not using IE, but you are and so you must update, do it or be vulnerable!