Strawberry Marshmallow might not be good for kids- too much sitting around and talking, not enough stuff happening. Same thing with Hanamaru Youchien (the amount of NGE references and the sister with bro-con would indicate it's intended for an older audience).
I heartily second Sailor Moon and Cardcaptor Sakura, provided you can find them (I feel like they're out of print).
Fruits Basket | Anime-Planet
Kemono no Souja Erin | Anime-Planet
(I don't think this got a physical release, but it is
Mahou Shoujo Tai Arusu | Anime-Planet
Princess Tutu | Anime-Planet
The first Fullmetal Alchemist series might go over well, as would pretty much any Ghibli movie.
Also: the Chi's Sweet Home | Anime-Planet
manga is being printed in english, and it's supposed to be really good/cute