There's nothing wrong with leggings per se. But let's get one thing straight: Leggings are not pants. I repeat: Not pants. If you're wearing leggings, we shouldn't be able to see your behind, not when you're standing up straight and not when you're bending over, either.
Leggings are meant to be worn with a dress or long shirt to ensure your fanny and hips are covered. And we don't mean an oversized college sweatshirt or T-shirt, unless you're staying in to paint the spare bedroom. To make the ensemble look nice, wear leggings with a tunic-style shirt or an age-appropriate dress with boots. And to be safe, don't wear your leggings to work, since they're not business appropriate. Save them for drinks and dinner with your hubby or with the girls!