Copper Chimney and the other restaurants in the chain (zaras "tapas bar", don pepes tex mex, etc) are overpriced crap. You can get far better anywhere else.

If you're staying at the Chola Sheraton one of the best you'll get is Bay Leaf (almost across the street, look for a "chaat" place called Gangotri, which is great for sweets / snacks, and there's a tiny lane next to it that you walk down for a couple of hundred yards, Bay Leaf is on your left).