root zone on a nameserver which cannot reach root-servers

[blrmaani]

We have a DNS server setup where all zones are either slaves or forwards to a internal DNS servers which resolves external names.

Questions:
1. Do we still need a root zone (type=hint) ?
2. What is the side effect of having root zone when our nameserver cannot reach root servers? (additional load on DNS if yes what percentage?)

Thanks
Blr