Help! Configuring BIND 8.22 on domain-less system

[Robert La Ferla]

X-no-archive: yes

Dear DNS Gurus,

I need some help configuring bind 8.22.  I have a Linux server that
connects to the Internet via a cable modem.  The server (onion) receives
it's IP address via DHCP.  This server acts as a router/gateway for
Windows 98 clients (potato and carrot).  The clients use the gateway for
DNS.  The server uses the ISP's DNS servers in turn.  This all works.
What I can't figure out is how to add local hostnames (visible only to
the LAN)  For example, I'd like the hosts "potato" and "carrot" to be
able to access "onion" by name.  They currently have to have this set in
a hosts text file.  I want this to happen via DNS.  Lastly, I'd like the
DNS server to cache previous host lookups for performance.  The other
thing I can't figure out is whether I really need a domain name or
not.   If I do, which one should I use?  I have registered domain names
at my disposal but the gateway doesn't have a static IP address.  Should
I use the ISP's domain?  Use a fake domain?  Does it matter?  Help!

Robert