Undoing an update to Ubuntu 9.10

Updating from Ubuntu 9.04 to Ubuntu 9.10 solved the sudo-cide trouble described above but posed its own problems:  the VGA output to a second monitor or a video projector didn't work anymore on my Toshiba Portégé R600.  Google gave a bug thread with the recipe to set a parameter nomodeset to the kernel and these grub parameter instructions showed how to do that.  It helped, but the projection kept quitting in movies.  Projecting is an important part of my work and probably for many others, but this bug seemed to get no attention.  So I eventually decided to reinstall Ubuntu 9.04 "cleanly", meaning a full disk wipe.  This reinstall was also problematic.  The top Ubuntu website (google install ubuntu) offered only the offensive 9.10 version and the supposedly stable 8.04 version, but the disk that I burned with the latter gave endless CD-reading noise and weird video, and made the grub loader contain only an eternal memory test.  Eventually I found Ubuntu 9.04 and then found that one should not, after the F12-depressed Toshiba startup and CD-icon selection with the cursor, cursor down to the install choice but instead must select "Try Ubuntu without changing your computer" and then click on the install icon that appears after the lengthy Ubuntu startup.

I then made the mistake to follow the recipe below from this Ubuntu forum thread:

  To replicate your packages selection on another machine (or restore
  it if re-installing), you can run this:
    dpkg --get-selections > ~/my-packages
  This will save a file called my-packages in your home directory. 
  Make a backup of it, install the fresh release, then restore the 
  file "my-packages" to new home partition and run this code in the 
  terminal:
    sudo dpkg --set-selections < my-packages && sudo apt-get dselect-upgrade
  It will download and install all the programs for you, except those
  that you installed manually, if they are not in the new repository.
  Then restore your backup of /home so all your programs settings
  will be as they were previously.
which deselected network-manager-gnome and so killed the nm-applet wireless, and with that any further downloading.  Remedy:  yet another reinstall, without such package recall but instead using my notes (posted above) on installing Ubuntu 8.10 to find which packages to reinstall and how to tune many settings and adjustments (such as the shell choice).  An unpleasant multi-day effort to re-invent this wheel, but eventually successful.  I now wonder when or whether ever to update Ubuntu in the future.  Is the recipe not to heed October updates?

Another quote from the same thread:

  Call me old fashioned, but I still don't see why I or anyone else 
  has to become an expert at saving this and that, tweak the other 
  and tweek the same, stand on your head and drink a pint of beer 
  from the far side of a glass, just so you can upgrade your 
  Ubuntu 9.04 to 9.10 without any problems.
  I just want to use my computer..... not program the damn thing!
Wouldn't it be nice to have an "Undo Ubuntu update" button next to the "Update Ubuntu" button in the update manager?