Welcome. Are you saying your ISP crashed, thus your internet connection died, part way through an online upgrade (by clicking the icon in Update Manager and going from 12.10>13.04)? If so, that is not good.
What happens when you run the regular update manager? Could you please post any error messages you get when you try a regular update? If nothing, and/or also, run these commands in a terminal one after the other, pressing return in between:
Post any error messages you get, particularly after the 'upgrade' command.
sudo apt-get update
sudo apt-get upgrade