Arkose: Right-click on the update and choose Hide update; it will then stop showing up in Windows Update (hidden updates can be restored from the link on the Windows Update sidebar).
I saw that option earlier, but I thought it only visibly hid it but would still install anyways. Much thanks for the solution. I'm still baffled as to why it tried to become a mandatory update after installing Windows Movie Maker, that update had always been optional for me since I built this PC in 2012.