Well if by C drive you mean /root partition then no you cant just backup your root partition. Things like usrland apps and /etc configuration files are all items that most people like to back up; at lest generally. Dump/Restore works great on BSD systems. If you are wanting a more universal way to "clone" your hard drive the dd command works wonders. Heres a small example:
http://www.linuxweblog.com/dd-image