Simply dig out the area underneath the house. Unless the base of the house is made of gravel or sand, the house should float when you remove the blocks under it.
There is no such thing as 'straw' in Minecraft. So you can't.
you make a house with wood dirt leavs
There is no way to do it.
you can, but if your house is in the nether, your bed will explode
Light up your house and kill all the bats.
You build your own house and you can find NPC villages in the world
try a site called planet minecraft, there are lots of good minecraft resources there.
you can put up a sign that you can make out of wood and put it at the front of your house
No, it's only available for download.
You destroy it and walk away.
You can create a bathroom in your Minecraft house by building a big, roomy section in your house, preferably accessible from your bedroom. Now all you need are the bathroom furnishings.
Rootbeer float