Go to %appdata%. You will see a file called wallet.dat. That file contains the private key. You won't be able to read it using text editors however. You can either use blockchain.info to use the online wallet by going to https://blockchain.info/wallet/import-wallet or use pywallet to extract the private key before importing into electrum or multibit.I don't personally recommend blockchain.info after so much security glitches but you can still give them a try, they are still okay for a quick spending.
Thank you so much , I just hope all will be fine while exporting them and the Reindexing didn't finish yet .
