To beat a dead horse, pick up Mastering Perl/Tk by O'Reilly for an awesome Perl/Tk reference manual. Or read the official/web documentation. The Registry stuff will be covered heavily in the Win32 module documentation, but it sounds like you will want to implement your own registry editor to get the "click and select" functionality you want. Given the way the question was posed, it seems like you would want to persue a few other programs before tackling the registry and Tk. They are easy, but they require understanding of a few concepts you may not have picked up yet -- references, modules, callbacks, etc.