I think Zumba is a great option. Would also recommend some slow paced yoga classes- this is how I began getting in better shape. Yoga helped me to realize that no one is paying nearly as much attention to me as I thought! It helped me get more confident so I could start trying out other more challenging classes and finding what I enjoyed the most. I haven’t been to any of the Y facilities on that side of the river, but I can tell you the northside Y is super welcoming of people of all abilities. I imagine it’s similar at all facilities. Good luck!