I added too many add-ons at one time and had to disable them all.
In doing so the menu and toolbar were removed.
I was left with the harley-davidson theme and one tab.
I could add a tab, book mark a tab, that's about it.
so, i tried re-installing. no change
i uninstalled, lost all my plugins, oh well... this time i'll be more conservative with my plug-ins
apparently multiple menu and toolbar plugins did me in
installed upgrade to 3.5.3
got a window with only a quarter of it displayed (upper left), and no response at all
uninstalled firefox, deleting my add-ons, reinstalled 3.5.3, works fine
lesson: disable add-ons before upgrading, but not all at once.