|Ruby/Gtk Installation & setup help|
Add Gtk to an existing MinGW-based Ruby interpreter
Now you should be able to run the Ruby/Gtk examples from the book and from the doc/ruby/gtk-0.27/sample directory.
If you want to make the Gtk libraries available to applications other than just your Ruby interpreter, you can copy them to your system directory, which is typically C:\WINDOWS\SYSTEM32 or C:\WINNT\SYSTEM32. (The book erroneously points you to SYSTEM; this generally works okay, but is really intended for compatibility with some older windows applications. SYSTEM32 is preferable.)
Note: If you're running the MinGW-based interpreter under Windows 95, 98, or ME, then you must copy the Gtk libraries to the WINDOWS\SYSTEM32 directory, or the interpreter won't be able to find them. This is not necessary if you are using the Cygwin-based interpreter, or have Windows NT, 2000, or XP.
Files kept hereSelf-contained (unzip and go) Ruby interpreter packages for Windows, including Gtk support