Following up on my own thread. Did some more research online and first found a free Jackie Chan movie. Not ninja, no. But the girls like the fact that he is "Monkey" from Kung Fu Panda, and a lot of the fighting was very reminiscent of that film (did JC choreograph those fights?) So, "Drunken Master", good introduction.
Still not Ninja. Ninja movies are pretty violent, but found Shinobi No Mono online from 1962. Liked it very much, not too violent and definitely not graphic. And it had the requisite Ninja masks.
I still like watching kung fu better. I studied Aikido and Iai Battu Jistu (Japanese sword discipline) for years, so I like watching the sparring and the sneaking of ninjas interests me less, but the plot in this was very good. Highly recommended!
"She is a mermaid, but approach her with caution. Her mind swims at a depth most would drown in."