We just had a wonderful meal at Tablo de los Santos within the Hotel St. Francis which I posted a review of. Their lounge, Secreto, serves up some of the best and creative cocktails you'll find anywhere. We happen to like the bar at the Anasazi, but the dining room seems way too stuffy for our style.
We also really like the patio at the Inn at the Loretto, or Luminaria. The food at Luminaria is quite good also.
The courtyard at the Palace Restaurant is really pretty and the new chef there is from a legendary place in Taos, the now defunct Joseph's Table. They serve food late and its really quite retro Santa Fe, if there is such a thing. Red velvet wallpaper, lots of history, local color, etc.
The Staab House, which is the lounge inside the La Posada resort is really historical and quite nice also.
CasaAzul nailed a few really good, old local institutions, with the exception of Maria's, which I personally can't stand.