Is this one of your first trips to India? I ask because I have a nifty list of precautions/preparations for us US-Based folk to note prior to going there. PM me if you want a copy.

As for covering DEL, I'm no expert on the city, but 2 days is really not sufficient for any Indian city IMO. Try to hit the main tourist spots, but also be aware that those areas will be frequented by some unsavory folk looking to rip off/rob foreigners.

I'm not trying to be morose; I'm just trying to give you a heads up to be careful, as you would in any new foreign city, India or otherwise. One of my worst experiences in the world happened in Madrid, just because I wasn't careful enough. And Madrid is my favority city in the world. Just goes to show...