>What is the relationship between these? That is, I'm wondering if there's a minimum NT/SP version to handle a USB port & connection. I can find nothing in MSDN on this...

Hi Bruce,
I noticed in the docs for my New Toshiba laptop that they stated I had to have atleast SP3 loaded before installing my USB zip drive. I also know Win95 requires release B for USB... and I believe release B and SP3 were relatively close on the timeline. HTH