Thanks for the post. We may be able to force Windows Installer to run in safe mode by altering the registry. However, let's first see if deleting the offending driver will resolve the issue.
Click Start > Run > type or paste C:\Windows\System32\Drivers. Scroll down the list of drivers and locate klif.sys. Right click on the file and choose "Copy". In a free space on the desktop right click and choose "Paste". Go back to the drivers folder where you copied klif.sys > Right click and choose Delete. Confirm the deletion. Reboot the computer and see if it will boot in normal mode. Post the results.