*Edit* I'm so sorry about this, it was quite noob-ish of me. This was my second day playing Minecraft so I was rather confused about, well, everything.
Do you realize that you have to use an image hosting site to post your pictures and not directly from your computer? As for the dungeon, I have seen it before.
This happened because water spawned first in the terrain generation, also you cant even see the pictures you cant just take them on your computer you have to put it on a image sharing site; such as imgur.com. Also its normal to have the walls not 100% moss stone.
*Edit* I'm so sorry about this, it was quite noob-ish of me. This was my second day playing Minecraft so I was rather confused about, well, everything.
"Oh wait, Your saving it for the spur?" "You dont love me then" -Curly