I start the software upgrade application, press check and Ubuntu 12.04 software upgrade does not show 12.10 upgrade on top.
The only way to upgrade seems via CD???? Upgrading to 12.04 worked that way but not to 12.10.
you have chosen to upgrade only LTS, or this is the default configuration with any Ubuntu LTS releases.
check your preferences, and change it as follows,
software sources > updates (tab) > "notify me of a Ubuntu version" > choose "For any new version"