You spawn in a plains biome facing a swamp. Go ahead to the tiny island which is closest to you (in front and to the left) and then enter into the cave entrance with iron ore on the surface. You will see some cobblestone once inside the cave.
Dig through to reveal a hidden zombie spawner. Take out the zombies or even better, light the room with torches, and then get loot from the chests. There is a fair bit of food to keep you focusing in important stuff ofr the first few nights in your Minecraft world if you choose this seed.