[Gtk-sharp-list] Opening / Closing Windows

[Met @ Uber]

Within a glade file I have a Window widget which I don't want opened
until a specific event.  Upon that event I want to show it (.Show()
presumably) and then on closing the window by hitting the X or by
clicking "Close" I would like to destroy it.  Since this is an applet,
I'm guessing for memory purposes its better to create the Window and
then destroy it again?

Simply put, what would be the best method to open/create and then
close/destroy a window which is part of an Applet (something that is
long running) and defined via a Glade XML file?

Thanks in advance,

~ Matthew