What do you plan? Use Veritas to restore? No.
It is recommended you use the swing server method, you build servers from scratch then join this svr to existing domain, run dcpromo, move FSMO roles to this svr, then install exchg 2003 server and join this new exch svr to the existing exch 2000 organization, then gradually move mailboxes, public folders or any system folders, and roles like RUS role to the new. After that decommision the old svr. The beauty of swing method is the low risk of downtime, and the ability to move everything in time which not a busy hour.