Okay, well autohotkey's site has a brilliant getting started which will cover this through and through, obvious advantages are, ability to add gui, in depth file commands, pre-programmed routines to work with complex strings/files/reg info/whatever else. But yes, i've seen the wall that's hit there. Though i've found a solution, i can't test it myself because i'm running vista(eww), but it's one that will do the job:
http://www.pctools.com/guides/registry/detail/214/
Give it a go and get back.
Cheers,
Jamey
Edit: we hit that link at the same time