How to Truly Copy Minecraft Worlds?

I like building in Minecraft and I want to use the towns I have made in older worlds and make direct copies of them. What I mean by copies everything from that world is copied not just the seed. Sadly, the copy function in Minecraft does not work.
I also don't the purpose of the recreate button. I'm using mods for 1.6.4 and I want to create two copies of my favorite world. One for the vanilla updates and the other for me to play in survival and to use my mods. Help please. I could elaborate more if it pleases!

MCEdit is exactly what you're looking for. You can take anything you want from one world, and place them into another world.

or if you're talking about making a full identicle copy of your world, you can simply go your minecraft saves (not in the game client, in the.minecraft folder) and very easily make a copy of the save file. (just right click the save file, press copy, and paste it somewhere else)

I don't know, but I think the Bukkit allows you to install mods that allow for copy-pasting. Sorry. I know that the help is often very difficult to find for specifics like that. I'd try youtube or google search, and then try the videos link.

In the end, however, you might have to go to the bukkit forums or the minecraft forums.

You can also copy the folder.

Head into your Minecraft folders and look for a copy of the world's folder. Copy and paste it right back into the same place and most operating systems will recreate the folder with a (1) or something like that appended to the end.

Minecraft will consider this a separate world.

If you operating system doesn't want to append, it just wants to overwrite, copy the world save into another folder, rename it, then move it back to the saves folder.