I really like going to malls and shopping centers when I can (sadly not often due to my circumstances), and a few malls within my area are all quite active.
The first one is the closest to me but also the most BORING imo. It's an outlet mall and it's almost nothing but chain fashion stores. There are a few stores that are semi-interesting (hot topic being one of them) so unless every other mall was nuked from existence, the outlet mall wont be my first pick for hanging out.
The second mall is somewhat close to me (20 mins away). I actually haven't been there a while but last time I was there (a few years ago) I was dragged there with my parents and it wasn't that interesting. I did hear a few new cool stores had opened there, such as a DND(?) store and some "cutsey" shops.
The third mall is by far the coolest mall I've been to, problem is it's SUPER far away. This is the only one I will disclose the name of due to privacy reasons, and it's the Stonebriar Center and I LOVE the place. I was visiting family when my cousins took me to the Stonebriar Center and i loved every square foot of that place. tons and tons of interesting stores around, such as a lego store, cute accessory stores, and a record shop. I even took a few pics! As you can tell, it's super active and bustling.
Honorable mention: Antique mall. It's really an antique store thats roughly a third the size of a walmart and has a lot of booths. i love it so much!