Good grub walkable from the Hyatt Regency Downtown?
560 is connected to the Hyatt Regency. Have been up for drinks and to enjoy the view once, and I imagine it can be casual for happy hour. You do have easy access to the light rail via Union Station. West End is walkable, but you will get touristy/chainy type food, and you can count on the same if you head up the red line to Mockingbird Station.
Here is another recent thread with a poster that stayed at the Fairmont (2 blocks north of Akard), with lots of great suggestions.
Don't know of much for walking and eating within that immediate area, but you are just a short walk from catching the rail to various part of the metroplex (including FW - once there, you'd have to relay on a bus/cab to eateries)
I'm not familiar with the various light rail stops within Dallas, except for Mockingbird station which has a number of restaurants - perhaps someone will be able to fill in the blanks.
Here's a map of the rail (DART) in Dallas. The Hyatt is located where all the lines converge. http://www.dart.org/maps/printrailmap...