If you want to change the look of your windows in Puppy linux you can install gtk+2 themes in:
Download the themes from this web site http://gnome-look.org/ decompress the contents and move it in /usr/share/themes. Themes are activated from the file /root/.gtkrc-2.0 which recalls the themes used in the first line:
include "/usr/share/themes/Country Oak/gtk-2.0/gtkrc"
utilizes the Country Oak theme that resides in /usr/share/themes. If you want to use another theme change this line with the name of the theme that you wand to use. Please note that with the jwm configuration program that comes with Puppy linux this change is automatic.