I was just invited by the birthday girl to "hold the date" for her 90th birthday. She is arranging it, but wanted some suggestions. This would be a Saturday lunch in May for about 25 people. She was looking for a place with good food where people can mingle (at least for part of the time) instead of just sitting next to one person for the duration. I would imagine that at least half the people would be around her age and most of the others in their sixties (her daughter's age). She lives around the UN, but I would think any place in Manhattan accessible by mass transit or taxi would be fine. She doesn't have a lot of money, but has a lot of pride and would probably would spend (within reason) whatever it takes.
[A few years ago, I would have suggested René Pujol. They had a private space with a cocktail hour for mingling and then a sit down dinner. ]