Dinner near the Fillmore Auditorium
How close? One of my favorite restaurants in the area is Fresca, but it's several blocks up closer to Fillmore and California. I actually just took a friend for lunch, and she said it was her favorite meal of her entire visit.
Here are some photos: http://www.chezpei.com/2008/09/fresca...
There's also a Korean restaurant on the corner of Fillmore and Geary, not more than a block from the theater. I still have not been, but a Korean friend of mine took her mom and they both said it was fine though not amazing.