That important GCSE work, if you want to copy it off the hard drive in short order so you can print it out on some other computer, get a Ubuntu Live CD, (Linux on a CD) guidance below;
Use Ubuntu Live CD to backup files from your dead Windows computer,
and use that to copy the work onto some external drive, USB stick or similar.

I assume you have no backup of this coursework.

Where did the Win 2000 interface come from?

Can you boot the system into Safe Mode? If so, follow Grif's instructions in the link below to download Malwarebytes' Antimalware on some other system, copy it and it's update files to a CD, use that to copy the files to your system in Safe Mode, install it, run it, update it manually, and then run a full scan. Link:

But that Ubuntu Live CD work is the first step in this.