Belgrano R is a fantastic area, though it's a bit distant. Recoleta is indeed upscale but can be a tad touristy. I recommend checking out Palermo or Palermo Chico. I've been staying in Palermo for three months, and it's been wonderful! It's very family-friendly with numerous shops, restaurants, and grocery stores. It's also close to parks and the Ecoparque, and just a 15-minute walk from Palermo Viejo, where you'll discover quirky and unique shops.
Palermo not only provides a sense of security but also a warm and welcoming atmosphere. When dining out, the waitstaff makes an extra effort to interact with children, adding a friendly touch. As an American, mentioning my origin often leads to locals practicing English, asking about the U.S., or sharing stories about their relatives in the states.