Learn a scripting language called Perl. It's super simple and extremly powerful. Learn about WMI as well. if you really want to have power, get a compiler and write your scripts into little programs. then you don't have to have the script engine turned on, or installed.
honestly though, scripting is going by the wayside. it's getting to the point where even allowing .vbs and .wsh files to run is a massive secuiry hole, so most places either turn it off or remove it completely, as we do.
it was blocking your access to the registry, so it couldn't see it. The Script calls out to regedit so it's not going to enable it to run if it's been disabled.