I still can't see the difference in your screenshots :-)
However I have noticed that changing the font rendering in System->Preferences->Appearance ->Fonts->Rendering does not have impact on the OOo fonts in the menus but does on gedit and others
It seems openoffice does some font aliasing of its own which overrides the font aliasing done by the windowing system : Tools->Options->View>font aliasing
end result is indeed that there can be a difference between the font rendering of most programs on ubuntu and open office which is not ideal
I still can't see the difference in your screenshots :-)
However I have noticed that changing the font rendering in System- >Preferences- >Appearance ->Fonts->Rendering does not have impact on the OOo fonts in the menus but does on gedit and others
It seems openoffice does some font aliasing of its own which overrides the font aliasing done by the windowing system : Tools-> Options- >View>font aliasing
end result is indeed that there can be a difference between the font rendering of most programs on ubuntu and open office which is not ideal