Then where do you get them from
The "Disc", would likely be the Windows 10 installation media, which can be obtained from either of these two resources.
http://www.microsoft.com/en-us/software-download/techbench
OR
http://www.microsoft.com/en-us/software-download/windows10
Once you have the ISO you can use ImgBurn to burn it to a DVD or Rufus to burn it to a USB ThumbDrive, from which you can boot your computer.
I am not an expert but I've used the technique in this article to enable the hidden Administrator's account offline from the command prompt, booting from the installation media.
http://www.howtogeek.com/75470/how-to-enable-the-hidden-windows-7-admin-account-using-the-registry/
The article is based on Windows 7 but will work the same on Windows 10 the only caveat being when you load the HIVE
%windir%\system32\config\SAM
You will likely need to use C:\%windir%\system32\config\SAM
because it will auto default to X:\ which is your DVD and you'll get a "being used" error.
Hopefully this will allow you access to your computer and by logging in with the hidden "Administrator's" account you should be able to make password changes as necessary to problem accounts or at a minimum, create a new account, that you can use to retrieve your files into. Make sure it is created as a member of the local administrator's group and not a standard user.
I know it works, because I just did it on my Windows 10 machine in a test run.
Just read the article carefully, so as not to make things worse.