The issue has been resolved. I spoke with Dell Tech Support and they had me simply insert the Windows 2003 SBS installation CD. I clicked on the "Install Now" option and the "Continue Setup" icon soon appeared on the desktop. I just finished the installation that I began last June, and the Server Management console was then present along with the Add License Wizard. I added the licenses and everything seems to be working fine. The Dell Tech first told me that I would have to re-create my staff's user accounts and also rejoin all of our computers to the domain, but thankfully that was not necessary.