Windows server 2003 restore

We would like to do a restore of a Windows 2003 server.
It's a domain server, on a 1-server network.
Before the dive crashed, and lost everything on the C: drive, we backed up the C: drive, using ntbackup, and also backup exec.
I've read that we should first reinstall server 2003 from the CD, similar to before, but not join a domain at first. Then run the backup software - setting it to overwrite newer versions with old.
We're wondering if anyone has a similar experience? Is the backup of the C: drive good enough to restore our active directory, software licences, etc?
Any help would be apreiciated.