My minecraft world on my PC has stopped working. Every time i open it my computer says that java is not responding. This is the world where I keep my redstone things and I really want to find a way to stop it from crashing.
Well, you probably don't want to hear this, but you may have crashed your map. This is not unlikely after the game crashed or got set to hibernation or something.
You have got the chance to restore at least the most of the world. There may be just one or a few chunks crashed (which are definitely gone forever) and you may remove them manually.
At first download MCEdit and install it. MCEdit is a tool to modify your schematics or even whole worlds. As soon as you load the savegame from your .minecraft folder, you should see your world on the screen. (This may last a few seconds to load, dont worry)
There should be some Chunks marked as crashed. Rremove them (for example by selecting them with the mouse and pressing entf aftwerwords.
Well, you really should watch this video before you delete your whole world by fail :P