The network name will be identical automatically, as long as you follow the steps in the order provided. A WDS cannot function any other way. The "additional information" is provided in the event you choose to configure the WDS manually. The requirements for identical wireless channels and security are just as important.
The base station names are arbitrary and have no effect on your network's operation. Choose names that make sense to you - "main base station", "relay base station", etc.
I assume you understand that configuring a WDS involves horrible compromises and should be considered only if you are using 802.11b/g-only AirPort Base Stations - older than six years old or so - and a "roaming network" is not an option either.
After setting it up and realizing how bad it was, I ended up getting an Airport Extreme as well as a 50 foot-long ethernet cord (taking no chances!). The wifi download speeds are 3-times greater with the Extreme now (from ~4-5 mbps to ~15 mbps) between opposite ends of my apartment and of course the ethernet helps. I should've gone for the Extreme a long time ago.