Ok so I figured out a solution:
Problem:
All Windows Server 2003 domain controllers (non R2 version) and all Vista computers. I previously deployed network printers through a VBS script. Now since we changed to Vista, it prompts for credentials when the script runs. Without the R2 version of Server 2003, I do not have the deploy printers function.
Solution:
Setup central repository for Vista Group Policies on the 2003 server. Configured the Vista group policy under User Configuration>Policies>Administrative Templates>Control Panel>Printers that is called Point and Print Restrictions. I enabled it, then cleared the two checkboxes to use specific print servers and using on specific machines. Under the installing and updating drivers section, I selected Do not show warning or elevation prompt. I then tested the script on several Vista machines after a gpupdate /force and all printers installed successfully without admin rights.