You can remove Internet Explorer 8 using the following command in a Command Prompt (Start > Run> CMD or Start > Search > Cmd):
FORFILES /P %WINDIR%\servicing\Packages /M Microsoft-Windows-InternetExplorer-8*.mum /c "cmd /c echo Uninstalling package @fname && start /w pkgmgr /up:@fname /norestart"
or
%windir%\ie8\spuninst\spuninst.exe
When the uninstall finishes, please restart your computer.