I have taken the huge world that is our full and complete world and cut it down to a square 1000 out from spawn. It essentially contains spawn village and the surrounds. You can download it and install into your local Minecraft copy and go nuts.
In other words: grief away! When you enter the map you should be in spawn. However if you find your self nowhere in particular then you have been placed in a random location - possibly the other side of the map in an unrendered section of the world. If that is the case simply kill your self to get to spawn.
Download it and extract the zip file and you should get a "World5" directory. The file is 53mb compressed and available here:
Copy it to your local Minecraft directory and away you go. On Windows 7 it is here:
If you already have a World5 just rename World4 or 3 or 2 or 1.
You will have no tools when you start but spawn is filled with chests containing all sorts of stuff. Just start exploring and find what you need.
Yes, at least one chest in spawn village contains a quantity ot TNT.
Yes, the stuff you need for a flint can be found in various chests.
Yes, the town hall does burn quite nicely.
Yes, the portals that did not work on the server are now working.