Refreshing Active Directory in Test Lab

We are testing Active Directory account provisioning in our lab and I
was hoping for some suggestions and best practices regarding
refreshing AD.

The lab will have two Windows 2003 DCs. My plan was to take one DC
offline line as an AD baseline. We would then run our account
provisioning tests. After each test we would like to go back to the AD
baseline.

Would the above be the best way to proceed?

Any suggestions or links would be appreciated.

Thanks,

Dave
.