Now what can I do to take the next step on configuring this beast?
I can't wget a file from it since its not the primary connection and trying to upload directly to the interface failed on my attempt - admittedly, might not have been the right build for this rev.
Main question: what's the right next step?
Secondary: What's the right build for this Netgear?
I had a very similar problem that I managed to fix, so I registered so that I could offer the solution.
First, make sure you have your IP set to some static address if it's not already. For instance, I had mine set to 192.168.1.17, and the default gateway to 192.168.1.1. Precise instructions can be seen here. Additionally, make sure to hold reset on the router long enough for the power light to be slowly flashing green (not orange).
After that, try flashing the wnr2000v3-factory_NA.img file from one of the earlier builds. You can look through them here. For me, ONLY the files from 03-08-12-r18687 worked, and nothing else. Every other version didn't play well with my router for some reason.