Topic: DNS Question

[Spawn]

Hello,

I was wondering EXACTLY what is necessary to make a registered domain name run off this server.  Is it possible to just register the name and give them the IP address of the e-smith server and have the domain name work?  
What is the deal when we start creating virtual domains?  
Can I do the same thing?  
Do I have to get my ISP to change their DNS for each domain name?  

Thanks in advance for any response.