In reply to cfer:
Your best bet is probably those recovery disks from when the laptop was new. You say it doesn't recognise anything - are you sure you're using them correctly? Sometimes you need to go into the UEFI/BIOS configuration, set it to boot from CD, then reboot with the CD in the drive.
A reinstall could be trickier. With windows 8.1, you may well not have a licence key sticker. Instead, the licence key is embedded in the UEFI/BIOS and windows should pick it up and activate itself when you install it. Of course if you wipe your current install and then this process doesn't work, you're up a certain creek without a certain implement, but that's apparently quite rare. To do a clean install this way you'll need a windows 8.1 disk/usb, these used to be available legal and free via digitalriver, but I think that may not be the case any more. There is a tool for making disks, but I haven't tried it.
I haven't checked them in detail, but you might find these instructions useful
http://www.eightforums.com/installation-setup/38486-need-help-formatted-gen...