You, or your computer, should not be using the recovery disk. This is normally a separate partition of the hard disk which contains a copy of your windows installation (OS) in case the main one gets corrupt or whatever, and you need to reinstall the OS
You would need to check that you are not using it for saving stuff, or that Windows is not using it for the page file, or system restore points, or that you don't have a back-up program running and saving to it
You will probably need to Google those terms and find out how to check depending on what OS you are using
Alternatively, it could be a virus writing/using the recovery partition