Apple/iPad File help

When I first got my iPad I tried to upload videos on it (.mov files). Well they didn't play (iPad 2, at least 3 years old). After one of the updates the videos appeared in my photo album, but now I can't delete them.

I've tried multiple ways of deleting the videos, but nothing works.

I've tried plugging it into my computer and looking for the files and deleting them that way, but they don't show up in any of the photo folders.

Anyone have any other suggestions?? Thanks.