Can you get achievements in Minecraft on the Xbox 360 in Creative mode?

I want to get the On a Rail achievement in Minecraft on the Xbox 360. Can I do this in creative mode or does it have to be survival mode?

It has to be pure survival for Achievements to be accounted for. You can't have Host Options on either, because it is still counted as having the game set to creative mode.

For your second question, it does not matter. If you have the game saved with Creative edits, it will count as a world created in Creative Mode. Survival Mode only You can't. But you can in Survival Mode

Survival Mode only

You can't. But you can in Survival Mode