You did not install the latin modern fonts: texlive-fonts-recommended
I don't think that package includes the latin modern fonts. The 'lmodern' package (which has ec-lmr10.tfm etc.) might also be needed. I'm not sure why texlive-context does not automatically depend on the proper font packages. Here are its dependencies: $ apt-cache show texlive-context Depends: perl-tk, libxml-parser-perl, texlive-pdfetex, texlive-base | tetex-bin, texlive-common (>= 2005.dfsg.2-1), texlive-metapost
I have installed the texlive and texlive-context packages from the ubuntu repository with apt-get.
It sounds like you're using the texlive-2005 packages from the feisty repositories. Those pkgs provide the 1995.10.10 version of context, which is almost two years old. Most features work unchanged, but if you want a newer version of ConTeXt (2007.04.17), follow the Ubuntu instructions on the wiki. -Sanjoy