Tooltorials

1. Instala un servidor con Windows Server 2003 64 bits (requerido para instalar Exchange 2007)
2. Actualiza el Active Directory tal como en el video
3. Promueve el nuevo servidor como controlador de dominio
4. Instala el servicio de DNS en el nuevo controlador de dominio
5. Mueve los roles FSMO
6. Instala Exchange 2007
7 Mueve los buzones desde el Exchange 2000 hacia el Exchange 2007

Para la migración del Exchange estos son los pasos generales:
# Make sure that the Exchange organization is set to Native Mode (no pre-Exchange 2000 servers)
# Make shure Exchange 2003 Servers have Service Pack 2, Exchange 2000 Service Pack 3
# Make sure that the Domain Controller that is the schema master in your Active Directory runs Windows Server 2003 with at least Service Pack 1 applied.
# If you have any non-English Domain Controllers in your Active Directory, you should also apply the hotfix mentioned in MS KB article 919166 to those servers, as you otherwise can experience issues accessing the address book via OWA 2007
# Finally Exchange 2007 requires that the Active Directory functional level is set to Windows Server 2000 or Windows Server 2003
# ExBPA version 2.7, which you can download at www.exbpa.com, includes an Exchange 2007 Readiness Check option
# Run Setup.com /PrepareLegacyExchangePermissions
# Run Setup.com /PrepareSchema
# Run Setup.com /PrepareAD
# Follow Exchange Server 2007 installation steps.
# Exchange Setup will create one Mailbox database and one Public Folder database on the respective server by default
# Exchange 2003 System Manager, then expand Administrative Groups > First Administrative Group > Folders > Public
# Open the property page of each public folder, then click the Replication tab and add the Exchange 2007
# Allow Anonymous users on the receive connector
# Create a new send connector from Exchange Server 2007 to internet
# Redirect ISA Server ports and rules
# Administrative Groups > First Administrative Group > Routing Groups > Connectors and right-click on the respective Routing Group Connector then select Delete in the context menu
# Exchange Administrative Group (FYDIBOHF23SPDLT) > Exchange Routing Group (DWBGZMFD01QNBJR) > Connectors
# Select Exchange 2007 as new RUS > Exchange System Manager > Recipients > Recipient Update Services
--------
Espero te sirva de guía.

En este momento no recuerdo muy bien cómo es la instalación de Exchange 2000, pero creo que te puedes basar en ella.

Saludos