Question : Windows 2008 Domain Controler

I've successfully migrated from windows 2003 domain to windows 2008.

Now, I've
1. Windows 2008 DC, DNS, DHCP
2. windows 2003 as a Member computer

How do i add windows 2003 as back domain and DNS?

3. All my Servers nerwork cable are pluged on Sonicwall and workstation on Switch , is it a good idea or should i plug all servers on switch?

Answer : Windows 2008 Domain Controler

correct...you will use those 2 domain controller addresses in your dhcp scope for dns servers