Hi richardmilburn,
Which version of operating system is installed on your computer?
The Graphics Interchange Format (GIF) images are widely used image formats on the web. They are compressed file which reduce the file size without degrading the visual quality.
If you don’t require the .gif files, you may delete the files from your computer.
a. Select the files by pressing CTRL+ A key.
b. Thereafter, right click on the window & click on delete.
Refer: Delete a file or folder
Hope the information helps.
Please post back and let us know.