EUREKA! I HAVE SOLVED THE PROBLEM.. For anyone inerested about those files that would randomly download as a plain "non mp3" document which wouldn't launch.. The problem was- All of those documents had one thing in common when compared to the others that downloaded as mp3s... The file names were too long... That's it. I just had to go in and rename the file (shorten it up) and add .mp3 to the end. The mp3 icon would appear as soon as I renamed it and clicked off of the title bar.. That simple. Shorten the name and add .mp3 to the end.

Thanks for everybody's interest.

itunes is available for OS 9.2.. thanks for the link!