I just found another thread in the Microsoft Answers forum
:What about when it is unavailable in the View Installed updates ?
FORFILES /P %WINDIR%\servicing\Packages /M Microsoft-Windows-InternetExplorer-*9.*.mum /c "cmd /c echo Uninstalling package @fname && start /w pkgmgr /up:@fname /norestart"
this removes the IE9 with the help of the command line. Credits go to Nadine K. (German MS Support Engineer).
Run it twice and reboot I ran this, and rebooted. Lo and behold! IE9 was gone, and IE8 materialized in its place! Now I don't know if I want to do the upgrade to IE9 or not. (I probably will, just out of curiosity. At least now I know how to trash it again, if need be.)
I still don't have much of a Windows Features list, so that part is still an issue, but I do have a properly-working IE now.