Dear Donn,
I also found Word 2008 to be painfully slow when my school first required us to "upgrade" several months ago. I am using a PowerBook G4 with a 1G RAM, OS 10.4.11. The tech support at my school tried many different avenues to fix the problem, including removing every speck on the computer related to Office 2004 or 2008, including preferences, identities, caches, and templates, and then reinstalling 2008.
The result has been the same, 2008 is fascinatingly slow, particularly when working with tables (up to 30 seconds to cut and paste a word), and even slower when dealing with Asian fonts. After several weeks of trying to make 2008 work, in the meantime falling behind in my own work, I decided to reinstall 2004 (which I had thankfully backed up elsewhere). Since then, my life is again happy and carefree with a word processing program that works.
After the latest update to 2008 came out, I decided to give 2008 another spin. Still slow. Indeed, considering how many of my coworkers, and the people on this site who have experienced similar problems, it surprises me that 2008 hasn't been pulled off the shelves in a product recall.
In short, if you want to save yourself some time and trouble, I would recommend that you simply return to using Word 2004.