what a little bit of research can find...
to revert to the default ubuntu (brown) screen issue the following
sudo ln -sf /usr/lib/usplash/usplash-default.so /usr/lib/usplash/usplash-artwork.so
sudo dpkg-reconfigure linux-image-$(uname -r)
a very good tutorial on how to further change that screen is here
ubuntuforums.org/archive/index.php/t-82835.html
(add http - apparently since I am a newbie... can't post links)
and, finally found the correct terminology - that screen is called by a program called usplash
Thanks all