Connect to NAS reomtely via SSH or Openvpn?


Which way is more secure? I have heard SSH is and also heard to goto dd-wrt and get a firmware for router so i can use openvpn.

here is the scenario:
I will be away from home within a few weeks for a few months or even longer; and would like to access my WD Mybook World NAS from my netbook. What is the safest way to do this? I am not going to use the default software I want another way. I have heard you can make a url for the NAS too.