Many thanks to Charles Hannum for solutions to my last two problems
to getting NetBSD up and running:

>    For the information, I'm using a WDC31000 1 Giga disk (2100
>    cylinders, 16 headers, 63 sectors/track).  I've got msdos on Cyl
>    0-1021, and BSD on 1023 to 2098.
> 
> Oh!  The boot block won't work right if the file system blocks
> containing the kernel are past cylinder 1023.  This is due to a
> limitation in the old BIOS interface.

Thanks!  I changed the partitions to:

1) MS-DOS: Cyl 0-993:

2) NetBSD: Cyl 994-2098:
   Root Partition: 994-1023
   Swap Partition: 1024-1079
   /usr Partition: 1080-2098

And it all boots fine!

One of the crucial things I had to discover to get everything working
(basically to keep NetBSD from stomping on MS-DOS) was to declare a the MS-DOS
partition in the disklabel.  This meant bypassing the installation script,
reading it carefully to understand what it was doing, and then modifying
/etc/disktab (with no editor, I did it by retyping it with
"cat > /etc/disktab" and adding a line to include the MS-DOS partition).
I then ran "disklabel" manually, did newfs and mounts, made a /etc/fstab
by hand (after flipping through some O'Reilly BSD 4.4 books that happened
to be nearby :-).  The rest was pretty straightforward.

Thanks again,
	Chris Perleberg