Hi Taffston,
Ah, you are a Gooner too :)
Thank you for the screenshot, that is a Windows Millennium installation disk, you should be able to use that disk to re-install Windows.
Backup any files you need to keep.
Insert that disk and restart your laptop to see if it automatically boots from the disk
If not,
1
Start the laptop, then repeatedly press the F12 key to see if that brings up the temporary boot menu, and choose to boot form that disk
2
If that does not work for you, start your laptop and repeatedly press the F2 key on your keyboard to boot into BIOS
In there, you will find the option to set that disk drive as the primary boot device, apply that setting and restart your laptop to begin the installation