A Viable Answer To The Above Problem!
In the hopes that this might help someone with the same (or similar) problem in the future concerning that which I reported above, please read this page:
http://forums.ilounge.com/archive/index.php/t-215612.html
The first respondent (all Windows users apparently!!) very aptly described the EXACT problem I've been having: freezing-while-syncing content from iTunes to the iPod.
On this page, two posible reasons were offered as to why. I tried them both. One DID NOT work, BUT ONE DID!
First, one respondent mentions the need to use USB 2.0 (true, and I have been) and then a new "2.0 cable". So, I plugged in the new cable that came with my 120GB and retired the one from my 5G 60GB. Nothing; same problem: a freeze while syncing after about 150 songs or so (of over 5100, no videos, no podcasts, etc). Back to the drawing board!
Another mentioned the possibility of a USB "power drain" hampering the syncing process. Hmmm. Is it possible that my G4 tower, loaded as it is, just doesn't provide ENOUGH POWER to the USB bus? Maybe. So, I shut down the computer, turned OFF the SCSI bus (I have some legacy stuff I need to run occasionally), and re-booted without it. GUESS WHAT??? I was able to sync ALL 5100+ songs straight through with NO freezes or hiccups!!!
So, IF you have similar problems syncing from iTunes to your iPod, shut OFF any unneeded stuff BEFORE starting the process. Looks like it'll save you from pulling out your hair like I was for several days!