Table for 12: vegetarian friendly
I would suggest Tabla. We were there at the end of November with a party of 8, several of whom are vegetarians, and the menu worked exceptionally well both for them and for the carnivores. The food is delicius, service is excellent (as one would expect in a Danny Meyer restaurant), and the atmospherics are very appealing. A party of 12 can be easily accommodated. Ask to be seated upstairs.
Photos of that dinner can be seen here: http://www.flickr.com/photos/11863391...
Do NOT do Dos Caminos... there's only one veggie dish. For a party of 12, depending on your budget (assuming it's family), you can do
Dhaba (for Indian) it has a more unique vegetarian seleciton than most Indian restaurants or
L'Annam if you want to do Vietnamese. Otherwise, Thai is always an option... I tend to like Pongsri, but if your family's a fan of the whole mock duck thing, there are many in hell's kitchen.
Tabla is pricey... if you do do it, go to the Bread Bar, not the upstairs. The food upstairs is not worth it. Bread bar is better.
Obviously, you are not aware that there has been a major change at Tabla. There is no more Bread Bar. The entire restaurant is now Tabla and the menu, which was reconfigured, is the same whether you dine downstairs or upstairs. The upstairs does retain a more formal feel since there are still tablecloths. As for prices, they are moderate -- closer to Bread Bar's than to the previously more formal dining room's menu. The website has been revised to reflect the changes: http://www.tablanyc.com
I would never recommend L'Annam because, imo, the food is awful. And Lantern Thai has far better food than so-so Pongsri.