Actually: "You probably know that you can kill Ourumov in the Silo, with the Gold PP7 or the Golden Gun. (Or kill him while you're Invisible) If you've done that then you've most likely found his briefcase and key. On the weapon screen, the key appears as a simple - dash. These two items were intended for additional objectives, probably from the game's beta stages. At one time, it is believed that Ourumov had some kind of blueprints or plans for the Pirate helicopter in the briefcase.
At another time, it's believed to have been Goldeneye satellite papers, possibly the one that is collected in Bunker 2. What doesn't make sense is that in the Beta stages, if you killed Ourumov, how could he be in the train later in the game? After you kill Ourumov, his key still has a purpose. Go back through two fuel rooms, and after the second, proceed straight through the hallway to a Silo with a missile in it. From your inventory, select Ourumov's key. As an item it does nothing. But, press "B" and the Silo roof opens! This is not a joke. It proves that the key has… or had a purpose at one time. To launch a missile? *UPDATE: If you use a Gameshark, you can walk through all of the doors and kill Ourumov. Then, you can open every door with his key. The Silo's master key?" - www.detstar.com
Not changing this until I own a Nintendo Wii. *PROUD PD VET*