Photos download in .zip format

If these are photos you took with a newer iPhone or iPad and Live shooting is active, it's normal.

There's no such thing as a photo that moves. What your device does is take both a still picture and a 3 second video. When you tap them on your iPhone or iPad, you see the video play and then the still photo.

When you download from iCloud, or even using Image Capture on your Mac to copy these photos to your computer, you'll get both a .jpg an .mov file for each image you've taken.

If you don't want your iOS device wasting space with these short video clips, turn it off by pressing the center icon while using the camera. Or, turn it off entirely in Settings.

Your iPhone is set to take a Live picture which is actually a short video. Open your iPhone (iPad) select Camera and look at the top of the screen for the icon that looks sorta like a bullseye. Click on it to turn Live off for future pictures if you like. I don't think there's anything you can do about current photos (easily).