Used to run a combo similar to that (original A7V + Win2K Upgrade). I was able to do so successfully.
You don't have to install Win9x first or anything, like bozo1 said you just need to boot from the Win2K Upgrade CD-ROM and then during the install process it will ask you to put in your Win9x/NT disc, for just a minute, just to verify that you own a copy.
Try the following...
1. Make sure the Win2K disc is in the primary CD-ROM
2. Make sure all IDE devices are on the VIA Southbridge not the
Promise IDE controller. (I always had to do this, but I heard that
there is a way to install with the Promise controller)
3. Change the boot order in BIOS to boot off the primary CD-ROM first,
and the Hard Drive second. The floppy drive can be last.
Everything should work OK from then. Good luck.