My friend started up a a new world this one time, and it had what seemed to be a perfect area. There was a water source, a few mine entrances, some pumpkins, etc. Lots of good places to build housing, but my favorite part about it was that it was naturally surrounded by mountains. As if the mountains were like natural walls. Unfortunately, there's no way to find out what seed your map runs on, and even then, he accidentally deleted that world.