MSHOME isn't a network as such, it's just a default workgroup name.

Replacing a server would involve firstly examining exactly what services
that server provides. There is no stock answer to this, if I was called-in to
replace a server (that I hadn't installed myself) I would be inclined to
spend some time making sure I understood exactly what role the server was
playing, and what the requirements for its replacement were.

The steps required  would also depend on wheter the server in-question is an
Active Directory controller, or not.  If the workgroup is MSHOME that tends
to suggest XP Home, though, in which case the network probably isn't
domain-based.

You can add a new server computer, provided it has a different name and IP
address from the existing one. Quite often this is a preferable approach as
it allows a more graceful hand-over from one to the other once all files have
been transferred.