As you say that you can hear your hard drive spinning, test it.
Go to your Computer Manufacturer’s website > look for your Computer’s specifications > find out brand of Hard Drive > go to Hard Drive Manufacturer’s website > find and download Hard Drive Diagnostic software and make a Bootable disk from it on the Computer you are using to get here, following their instructions > test your Hard Drive to see if it has failed.
And you can also use this Method to test your Hard Drive:
“SeaTools for DOS”
“SeaTools for DOS tutorial”
If it is OK:
See if this assists you with your Repair options.
“How To Access Advanced Startup Options in Windows 8 or 8.1”
“How to Boot to Advanced Startup Options in Windows 8 and 8.1″
There is detailed information here too.
And please read this method:
“How to Boot to “System Recovery Options” in Windows 8 and 8.1″
If you need Media for Refresh and/or to reinstall, read this information.
You can contact the Laptop/Computer Manufacturer and order Recovery Media from them for a small cost.
You can download and create your own Windows 8.1 Installation Media to reinstall the Operating System with..
“Create installation media for Windows 8.1”
A similar Tutorial which may also assist you
“Create Installation Media for Windows 8.1”
In the first screen of this very simple wizard, you need to choose the following:
Language. English – en-us if you’re in the United States.
Edition. Windows 8.1 (Core), Windows 8.1 N, Windows 8.1 Pro, Windows 8.1 Pro N, or Windows 8.1 Single Language.
Architecture. 64-bit (x64 ) or 32-bit (x86).
“How to Create a Bootable USB or DVD with a Windows 8 or 8.1 ISO”
With Windows 8/8.1 The Product Key on preinstalled Operating Systems (HP, Acer, etc) is embedded in the BIOS in the Motherboard, so that the lost and/or worn C.O.A. Sticker problem is no more.
When you reinstall it will pick up the Product Key and activate the system automatically.
If it does not, follow these steps:
“How to Activate Windows 8 and 8.1 by Phone”
“Get help with activation errors”
“How to activate a Microsoft product by using Microsoft Product Activation Center”
This information may interest you if you do wish to keep a record of it:
“Windows 10 Embedded Product Key Tool”
“We’re proud to introduce the immediate release of our newest utility for Windows users: the NeoSmart Technologies Embedded Product Key Tool. Designed for users of Windows 7, Windows 8, and Windows 10, our embedded product key tool will retrieve and display the Windows setup product key embedded in the BIOS or EFI, allowing you to store it for safe-keeping or use it to reinstall Windows with an official Windows setup image.”