Regarding colour, its all OK, but the design depends also on your body type, which we don't know. Skirt 4 wil certainly make you, and certainly your legs appear longer. Skirt 1 will make your hips wider. Skirt 3 is neutral and formal and is Ok if you have wide hips, because it will make them smaller. Skirt 2, I personally find too busy
#1 is OK. #2 isn't really my style but it's cute. I love #3 and it's very in style now, so it has my vote. I like #4 too It's very classy looking. I don't really think you could got wrong with any of them; it just depends on your style.