I like both stay-ups and ones that require garters. It depends on the length of my skirt/dress. For your white skater dress, I'd go with something in a natural skintone like sheer nude or beige and pair it with some white, or beige heels.
I like wearing the full stockings. It's easier and you won't have to worry about anything sliding down. Garters are kinda hard to work with and the ones that are supposed to keep themselves up might still fall. And for color, I'd say black for a nice contrast against the white, or white so everything matches.