gtk_widget_destroy "doesn't work"

[Ingvar Tjostheim <ingvar isafold com>]

Hi.
I'm pretty new with GTK, and I have a problem with gtk_widget_destroy.

I have a window with some option boxes and a combobox. When user clicks OK I want the window to go away for 
the application to create a OpenGL window and do other stuff.

My problem is that the window does not go away, but gets locked. The application continues with what ever I 
want it to, though.
The problem is the same if I use gtk_widget_hide.

This is briefly what the OK-button function looks like:

void btnOKClicked (GtkButton* button, gpointer data)
{

  //read which optionbox is checked
   ....

  //read what the combo box says
   .....

  gtk_widget_destroy(GTK_WIDGET(data));

  gtk_main_quit();

  startCom( read values..... );
}

And the function is connected this way:
  gtk_signal_connect (GTK_OBJECT (button), "clicked", GTK_SIGNAL_FUNC (btnOKClicked), window);