Hi sh0rty and welcome to the community!

Based on your pics, it looks like both boots fit well. I would assess the fit and the comfort of the boots. How do they feel when you walk in them? Are they comfortable? Also, if you're going to be doing a lot of bending (and who doesn't during the course of the day, esp. playing with and picking up your kids?), the shaft will dig into the backs of your legs. (I had to get used to that with my tall riding boots!) Personally, tho, I would go for the under the knee boots instead of the over the knee pair, especially since you mentioned you are looking for a wardrobe staple. Over the knee boots are a current trend and I'm not sure for how long. Tall riding boots look very classic to me (I LOVE THEM!) and are more versatile to wear with dresses, skirts, etc. But this is just my two cents and you'll have to decide on which one you LOVE wearing, which one makes you feel fabulous!

Perhaps the other ladies can chime in, too.