Sangria is closest and very nice. Bay Leaf is also close - very good food but occasionally you will find a waiter that is pretentious. Depending on your comfort level walking the streets and if you are looking for even more upscale then I would go with Cosmopolitan which is about 3 blocks away. Pricey by Allentown standards but the food is very good and the restaurant is nicely done. They are the only restaurant in downtown Allentown with a skydeck bar. If you are looking for a brewpub I would recommend Allentown Brew Works
Bay Leaf Restaurant
935 W Hamilton St, Allentown, PA 18101
Allentown Brew Works
812 W Hamilton St, Allentown, PA 18101
I was waiting for someone from the Allentown area to respond but I guess I will have to get things going.
You might look into Sangria on Hamilton which I think would be within walking distance. Friends in the Lehigh Valley have recommended it to us but we haven't had the opportunity to go there yet. I believe its Web site is www.sangriaallentown.com. This is the best I can do for Allentown within walking distance of the Holiday Inn.