Much like what happened in the post that I mentioned I had read, regarding this same topic, I myself googled my problem, and found a solution.
I googled this: "mpeg4 to avi converter"
There are many freeware converters out there in googleland, but I chose one that was offered on download.com, a place I have used before, a safe place where applications are virus tested before offered for download.
And the converter I found is called the Any Video Converter (appropriately enough), and it is the most downloaded converter at Download.com.
I installed it, easy to use, dragged my mpg4 quicktime video into the converters interface, picked, from a simple drop down menu, a dvd .avi choice, and it took about 8 minutes to convert it to the .avi file that matched the other chapters of this multiple 'toon download I have.
I deleted my version, dragged the new version to the folder that holds the .avi's in question, and ta-da.
So, if anyone reads this post, and has the same issue I have, I gotta recommend the Any Video Converter.
I am saved.
Thanks to the hundreds and hundreds of replies that I got, helping me in this matter..(he said jokingly)
But seriously, Thank you t0nee1.
I sincerely appreciate your help.
Until we meet again.....
(what a production for something I figured out myself, eh? ahahahaaaha)