My wife and I--both 50--will be visiting BA for the first time during the last two weeks of January. We want to spend a majority of our time exploring the city, will spend two nights at Iguazu Falls, and are looking for a low-key, chill-out spot to visit before returning to NYC. The travel agent suggested Punta Del Este, Uruguay, which is definitely not to our liking--the pictures look like a cross between Miami and the Hamptons. Any suggestions?

Why don't you try researching the smaller Argentine beaches?

Some names which come to mind: Mar de las Pampas, Cariló, Mar del Sur, Villa Gesell. Many others.

No matter which beach you choose, it will be crowded in January, however.

Have a great time in our country.

There are also a few hotels in Punta del Este that are not in that main zone and are fairly isolated. Check these reviews for the upscale ones, Mantra and Las Cumbres. May be more in line with what you're looking for.
http://www.luxurylatinamerica.com/lux_uruguay.html

Wherever you end up going, make reservations early. That is prime vacation time for Buenos Aires people and beach resorts get packed out.

Thanks so much to avrooster and globtrots for your suggestions. And I am sure I will have a great time in Argentina

I just returned from Uruguay and I was also turned off by the appearance of Montevideo and Punta del Este. Too big and commercial for me.

Instead we continued towards Brazil and rented a great little house at Punta del Diablo. We loved this little fishing village! It was a great place to relax at at the tail end of our vacation. You can check out more info at:

www.portaldeldiablo.com

Enjoy!