We have a client with 400 machines running 2000/xp on front end with NW6.5.4 and Zen 6.5.1

Each pc has dual logins, meaning, they login into novell, then login into workstation then get the desktop...each computer is not in the AD domain, but needs to be:

1. Once I add the workstations in the AD domain, can I use the MS GPO to manage them or better to use ZEN?
2. Do they need the novell client to run zen? If not, can I just map a drive to the novell servers via CIFS?
3. How is dynamnic user implemented in this scenario, vis MS GPO/AD or Zen?

what do most customer do out there with these number of workstations?

Any help is appreciated.