Well, I've figured out the difference, now I just need help backing out of it.
When I set user-level access in network properties the initial message was that the SAMBA server could not be found: "go ahead and save it anyway?". I said yes. Well, I should have said no and re-booted, logged into the SAMBA server and then set the Win98 boxes to User-level access. Then you don't get that message and setting file-folder sharing works.
So.. now how do I undo the 3 machines it took me to figure it out?