Thanks very much for your response.
(a) yes, I went to system --> restore. I also update the firmware, rebuilt the raid array as a RAID 0 array (thought maybe RAID 5 was just REALLY slow...)
(b) I have not yet plugged in to PC directly. We are on a gigabit network at the office, however I will double check to ensure
(c) I will attempt to use a different ethernet if (b) still does not produce adequate speeds.
The terastation is at my office -- so I won't be able to try these out until Monday. But I will post here after trying it out!
Thanks,
Mark