Initial domain and namserver

[cmendes0101]

I'm running into a bit of trouble with domains and nameserver stuff.

When installing ispCP should the main domain for admin.domain.com not be used for a regular website like domain.com? currently i'm doing that but not sure if thats correct.

Also I can't figure out how to get nameserver to work. I tried pointing the DNS from a registrar to ns1.domain.com / ns2.domain.com but it gives me nRRPResponseCode 541
Nameserver ns1.domain.com cannot be registered.

I looked at /var/cache/bind and everything seems to be in there.