RPC = Remote Procedure Call
Protocol that one program can use to request from another system in the network without needing to understand network details.
NFS = Network File System
Client-Server application that enables you to view and store, update files on a remote system as though they were on your own.
Either disable NFS at startup and check out the howto here for NFS if you want to know more about it:
http://www.tldp.org/HOWTO/NFS-HOWTO/index.html