Get:1 http://us.archive.ubuntu.com gutsy/universe python-genshi 0.4.3-1 [271kB]
Media change: please insert the disc labeled
'Ubuntu-Server 7.10 _Gutsy Gibbon_ - Release i386 (20071016)'
in the drive '/cdrom/' and press enter
What if you are unable to do this? or tired of running from room to room? there is a little change to do to save the labor.
Just comment out the line referring cdrom in /etc/apt/sources.list. In my system this is the line you need to be commented out.
deb cdrom:[Ubuntu-Server 7.10 _Gutsy Gibbon_ - Release i386 (20071016)]/ gutsy main restricted
There is a complete doc on the apt-* commands in