Restore Dapper after Edgy

[NoOp]

I'm sure that this has probably been asked and answered in the past for
previous Ubuntu upgrade/install problems with mixed versions, but can't
seem to find an comprehensive answer that tells how to restore Dapper to
it's original files after a Edgy abort. So here goes:

Situation:

After noticing that OpenOffice via Dapper is version 2.0.2 and after
updating to 2.0.4 succesfully via the OOo files, I noticed that Edgy has
2.0.4. So like a fool I was curious and decided to try the Edgy
repository version. What I didn't realize is that by doing that, the
Ubuntu OOo Edgy install also downloads and installs additional non-OOo
system files (lib6_2.4 etc).

I suppose that I created the problem myself by adding the Edgy
repository (main/stable) to my repository list to do the install. But
figured that I was only doing an apt-get install openoffice.org and that
it would only pull the OOo 2.0.4 files from Edgy. Not so, it pulled all
sorts of files in addition to the OOo files. So I abort the install --
unfortunately multiple Edgy (non OOo) files get installed on my system.
As a result locales gets screwed up, multiple lib files are now Edgy 2.4
etc vs Dapper 2.3, and so on.

So I uninstall OOo. In the process I discover that OOo is an integral
part of ubuntu-desktop, and if you uninstall all OOo (including 2.0.2
core) you also uninstall the entire ubuntu-desktop. In other words you
cannot uninstall OOo via Synaptics or apt-get without uninstalling the
entire dependencies.  Sounds a bit like Microsoft and trying to
uninstall Internet Explorer...

I notice that ubuntu-desktop should be installed before performing an
upgrade from Dapper to Edgy (was the same for other versions as well), see:
https://help.ubuntu.com/community/EdgyUpgrades
====
Upgrading using apt-get

   1. Make sure that you have ubuntu-desktop, kubuntu-desktop, or
edubuntu-desktop installed (depending on which distribution you are
using). *This is VITAL for apt to perform the upgrade successfully.*
          *
           Example:
              sudo apt-get install ubuntu-desktop
====

Doing so forces the OOo 2.0.2 components to be reinstalled as well as
some other components that tend to screw up existing configurations. Why
is that?

So, like others I'm sure, I'd like to simply restore my Dapper 6.061
back to it's original base files without having to repartition my hard
drive and/or reinstalling from scratch. It's ok to revert back to the
older 6.06 CD base OS files in the process, updates on the next reboot
will take care of that problem. However, it seems that once you get Edgy
lib files installed there is no easy way to back down to Dapper (that I
am aware of). I've even done a dpkg -i *.deb from my
/var/cache/apt/archives directory. And while that tends to restore most
packages & resolves most issues, it doesn't clean the system of Edgy
installed files.

Questions:
1. How to restore a Dapper system back to its basic files without
destroying any /home user data and having to reinstall and repartition
the disk? This seems to me to be a basic requirement of this system.

2. How to upgrade to the next Ubuntu version without having to depend on
ubuntu-desktop which installs seriously outdated files?

3. Why is Dapper 6.06x 2 revisions behind OpenOffice when OOo is an
integrated part of the OS desktop? Note: after cleaning out all of the
Ubuntu dated files (2.0.2) OOo 2.0.4 installs and runs just fine.

Suggestions/comments? I'm sure that I'm not the only one that has this
issue and has corrupted their system with mixed version files.