I got this to succeed.
Basically I performed the following (but not all in the same day):
1. Started Synaptic.
2. Selected a bunch of packages I wanted (took about 20 minutes to find and mark the packages).
3. Selected the "Download package files only" option.
4. Downloaded the files, which by default are stored in /var/cache/apt/archives.
5. Copied all packages from /var/cache/apt/archives to a DVD-RW.
6. Downloaded and installed pkgutils.
7. Opened Konsole.
8. cd to /var/cache (seemed like a good place to create a local repository).
9. Ran the mkrepo script.
10. Copied all *i586* packages from the DVD to /var/cache/src/rpm/RPMS/i586.
11. Copied all *noarch* packages from the DVD to /var/cache/src/rpm/RPMS/noarch.
12. In Konsole, cd to /var/cache/src/apt/pclinux/2009/base (created by mkrepo).
13. Ran the gbd script.
14. Closed Konsole.
15. Started Synaptic.
16. Selected only the local repository.
17. Created a new filter called Not Installed.
18. Selected all packages and marked for installation.
19. Installed all the packages (very fast when performed locally).
20. Copy/mirror /var/cache/src (local repository) to a DVD to provide a backup.
At this point I now can install a 2009.2 Live CD and then update the system to my preferences without consuming any additional bandwidth. That is pretty much the intent of remastering a new Live CD/DVD, but I needed a method to allow me to repeat multiple installations for learning purposes.
The process is not perfected. I need to add some packages to my local repository that I downloaded and installed, such as pkgutils and speaker-test. There probably are a couple of additional packages too.
Perhaps this information will help somebody. Feel free to improve the process for the wiki and update accordingly. Question:
Does anybody have a list of packages from a default 2009.2 installation? I want to filter which packages I downloaded and installed after installing 2009.2 but before I updated with my local repository. Should be a short list. I created a list from rpm -qa and diffed that with the list of packages in my local repository. Yet I cannot distinguish which were installed from the original 2009.2 CD and which were installated thereafter. I probably could create a temporary virtual machine, install 2009.2, create a rpm-qa list and then that would serve as a baseline.