Its very easy to copy the data from bluestacks to your PC.
Just download Astro File Manager and install it using bluestacks. Its android browser. After installation, open it. You will get a folder 'mnt'. In this, you will find the folder 'sdcard'. There you will find your data. For example, the data shared in whatsapp will be there in folder 'whatsapp'. Click on the file you want to transfer to your PC. Do not leave your click. if u want all the files select all Keep holding the same click. And you will get the option of 'copy/move' at the lower side of your screen. Click on copy/move now just go back at the starting of Astro File Manager , here u will find "Adminstrator Pictures" open it n just paste