You are in a lot tension because your Mac stopped responding ? There were many important files in the Mac drive that you don't want to lose. You are facing this problem may be because last time the system was closed abruptly and all the system files and files related to the Mac OS X has gone damaged. Sometimes the drive can also get corrupted and the system does not start. The first thing you need to do when the Mac stopped responding is to restart the Mac system an then you can use the disk utility to fix any of the minor problems of the drive. The last option would be formatting the drive and reinstalling the operating system. You would be thinking what about the lost data, that you can restore from the time machine backup. But if the time machine is not working then you can use the Mac data recovery software. It will do the scan of your Mac drive and show the result in the preview window where you choose all files for recovery or select some. When the files are restored you can use you Mac computer as usual. So don't worry when the mac stopped responding, fix it and download the software to restore Mac data.