It should definitely be "the tall young woman," not the "the young tall woman," though it's difficult to explain why in just a few words. But as a general rule, adjectives referring to physical size (big, little, tall, short) tend to be placed farther away from the noun.

Regarding the second sentence:

(1) Using "fragrances" and "smells" in the same sentence seems redundant.

(2) Seraph's suggestion of "radiates" is okay, I guess, but to me it sounds slightly odd to use this verb with smells. (Because smells tend to spread slowly in a cloud, like a drop of ink in water. "Radiate" would seem more natural to me if you were talking about the colors of the flowers, because the colors reach our eyes at the speed of light!)

I would suggest, instead:

"The lovely, bright bouquet of fresh flowers in his hand fills the air with the sweet and gentle scents of spring, and colors her soul with love."

(Seraph's version of the first sentence is perfect.)