Although my French is a little rusty, I think the first error is:
Configuring apache2.2-common (2.2.16-6 + squeeze10) ...
ERROR: site default does not exist!
dpkg: error processing apache2.2-common (- configure) *:
I imagine that "site default" refers to the DocumentRoot directory
specified in the apache2.conf file. Normally:
Make sure you have this pointing to an existing directory.