Upgrading from 3.12 to 5.1

486 200mb hard drive Novell 3.12.
No Original software
Novell 5.1 upgrade and a new computer ordered.
System runs a pos application so down time
is limited.
What is the best way to get Novell installed
on the new server?
I am also concerned about 2-3 years from now
if I have a disk problem and have to reinstall from scratch.

Thanks