thank you for your quick response, but when i right-click on the 'pc' menu button, i see no such option. there is only:
menu settings [which is only for changing the menu icon],
add/remove panel items,
remove menu from panel,
and create new panel.
i did just rename 'picasa.menu' to 'ppicasa.menu' in /etc/xdg/menus/applications-merged (so hopefully its parent-menu-thingy won't find it)
i'm gonna log out/in and see if that screwed it up