Novell is a Network Operating System, just like Linux and Windows 2000 / 2003 Server. Novell was the dominate networking environment in the PC / Mac world, until the mid 1990's, when Microsoft prepared NT 4 Server, and then Windows 2000 server. Novell handles printing, file sharing, web sharing, and a variety of things, but doesn't allow one to use the server as a substitute workstation like NT/2000 does.
Novell is still a robust network OS, but it has been superceded in almost all respects by either Windows 2000/2003 and various *nix distributions. The cost of deploying Novell is a bit higher because of the difficulty and sparseness of support as opposed to Windows or Unix/Linux.
If you are starting from scratch, and need to set up a domain and a new network environment, I would recommend against novell. However, if you are supporting a legacy novell system, I would highly recommend the latest version.