|If you work at a charitable organization I assume you don't want to buy anything. |
Most name brand computers come with a version of Windows pre-installed. Buyers do NOT follow instructions to create the backup disks to restore the computer to factory specs when needed. There usually is a restore partition on the hard drive that can be used to restore the computer to factory condition.
The method used to access that partition varies by brand and sometimes by model within the same brand.
Dell sometimes supplies disks with their computers that are basically Dell branded full versions of Windows. That appears to be what you have used.
You need to try to access the restore partition on the internal hard drive. Click on the link and follow the instructions.
Below is a second link to the HP site for your model Compaq. You can download a manual by clicking on the support and drivers listing.