-camilletom
If forced into a choice between FireWire and USB, choose Firewire. But hayduke is right - both interfaces are best.
The D2 you chose is an exceltentchoice. You can even upgrade the drive should you chooses (PATA interface). One thing about the D2 - it's enclosure makes for a good Faraday cage - e.g. resistant to e.m. pulses.
Growing up in the Midwest, I knew many who lost drives due to the corruption brought on my a nearby lightning strike - myself included.