Current update:
Ran all my files through Tag and Rename, as suggested.
In the process of importing all my files, this time via Music Manager which does this on the slow side, but it seems to do much better how I attempted this before, via Windows. So far, I've had FOUR files rejected by Music Manager, and it was for things like saving an mp3 at 48,000khz versus 44.1khz. I UNDERSTAND what the error message means, and can easily fix that, especially on four files (versus the THOUSANDS of errors I got last time out).
I'm at the most optomistic I've been about this project since I got the unit.
Silvio and Rick and Silverfox: thanks for your help.
Also: I'd like to participate on the denondjforums (both with questions to pose, and to "pay it forward" once I know what I'm doing), but the site doesn't view properly for me. In IE(8), I get the left half of any forum page on the left half of my display, and cannot see the far right, which sometimes leaves me guessing what's there. There's no scroll available, and changing the zoom doesn't provide the missing elements of the page, either. Firefox is a little better, but I have the same problem with it. Do I need to use my Mac and Safari to use the forums? (I haven't tried that yet.) I can screen shot any of this, if I'm not explaining myself well enough.