I have broken and partial upgraded system, it was attempted to upgrade from 12.04 to 12.10 some how things did not went fine, and in next consecutive months I kept using this system. Later on when ever I needed to install a package like bind9 or some thing or some package I always landed in trouble,either I select one by one which package or dependency needed to be downgraded or I do some kind of circus.It wasted a lot of precious time.
Is it possible to bring back the system from this state to a state when 12.04 fresh installation package were present.
Not reliably, whether the upgrade was successful or not. Attempting to do so would take an awful lot of time and cross-checking. I strongly suggest backing up everything in and under /home then do a wipe-and-reinstall, as the quickest and most reliable path back to the stable system you prize.