Windows 2k3 SBS… Upgrading server

Currently running 2k3 SBS on a system that we are quickly out growing.
Current setup involves 4 drives.
1. system
2. Exchange
3. Shared files and resources
4. Lab and system backups

Runs exchange for email, blackberry server, Nemx spam control, and Add2Exchange with Sql lite to broadcast Calendars and contacs.

New setup will run Raid 5 on 3 500’s with a much beefier CPU and Memory.
The question is how do i get my old server info on to the new one…… or do i have to start from scratch and lose Tons of calendar info, contacts, and stored Email?