openview is an entire suite of applications used to manage a network. From basic connecitivty to threshold and alerting/logging. Generally used as a MOM (manager of managers) where all the separate element managers report to openview via plugins or SNMP traps.
Very powerful and flexible, used by just about anybody with a good sized netowork (over 30-40 routers) that has an OPS center.
hope this helps...real network management is very deep and hard to describe in this context. I've never heard of network inspector so I can't comment.