Setting up separate network question

[Labitt, Bruce]

I've got to set up a secondary network on my Centos computer.  I need to
be able to contact the internet from my secondary network computers.
However, I really don't want the outside network to get into my
secondary network.  I have a high speed network connecting a cluster of
computers.  The external network is much slower than the secondary
network.  

I just want to ask the list if I've got this right.  

Let eth0 = outside network.  Eth1 = inside network.

I have dhclient running on eth0, so I can get an IP address for my
Centos machine.  
I need dhcp running on eth1 so I can give IPs to the internal computers.
Then I need to have iptables running on the Centos box.  Inside of
iptables will be a MASQ command to turn masquerading on.

I intend to use the file rc_firewall-iptabless-stronger given on
dranch's webpage.  I think it covers everything I need and is commented
well.

Is this benign to the outside network?  Do some networks block this?  I
will contact my network support people, but I wanted to know if I was on
the right track.

TIA
Bruce