Good questions- 1) It is a real firehouse with real firetrucks and firefighters. Not only are they equiped to fight fires in mcmurdo, they are also equiped for fires at the airfield. Hopefully before long the page on the firehouse will be completed. I have some guest webmasters that are trying to find time to put photos of the department and the equipment on the fire page for me.
As for penguins you can walk right up to them. Or more likely they will walk right up to you. The Antarctic Treaty applies here though. You cannot disturb them at all. Most of the time if you are still they will come look at you and be on their merry way. Touching them or harrassing them in any way could land you a treaty violation fine and a quick oneway ticket out of Antarctica.
Mount Erebus is very active but in a quiet sort of way. Most clear days if you walk out on the ice shelf or go to Scott Base (New Zealands Base) you can see a plume of smoke coming out of the top. What is unique about Mount Erebus is that the Magma pool is constantly recirculating drawing the cooler lava back down into the crater and replacing it with fresh hot lava. It occaisionally will burp little explosions of lava out up to a half a mile away, but most of the time it is just a pool of molten lava.
The other interesting Erebus feature are the Erebus Crystals. As the lava cools these are among the first crystals to come out of the lava. As the cooler lava is drawn back into the chamber the crystals don’t get hot enough to melt again. Instead they grow larger and larger. When the explosions hurl out volcanic debris, the cyrstals are thrown out too and litterly cover the area around the summit.