My favourite world that uses about 40megabites worth of space has become corrupted. Whenever I try to join I get in the for about 5 seconds then it kicks me saying "this world is corrupted, please go to bugs.mojang.com for help so I came, made an account in the hopes you could help me. If you have any advice please let me know. Thanks.

Update(rather soon): I just tried editing the world settings but the game crashed after I turned tnt explodes off.