Hotels:
Oberoi
Lodhi
The Imperial

Dining:
Indian Accent- Michelin spot in the Lodhi hotel. Can eat a la carte or do the tasting menu. All dietary preferences are welcome. Do not do the premium wine pairing, stick with the local wines, Indian shockingly has great wines and if you do the premium you are just paying to have French and other European wines that you may have at home. 
Spice Route - in the imperial hotel, really great food almost a blend thai and indian. we loved this spot and very convenient as we stayed at the imperial. get the cod (it taste like Nobu) 
Olive Bar & Restaurant - really amazing food, one of our favorite meals, the veggie dishes were incredible. request the patio! 
Perch coffee & wine bar 

To do: 
Khan Market
Humayans Tomb
Qutub Minar
Lotus Temple
India Gate
Presidents House
Old Dehli- spice market (bring a scarf, the pepper in the air gets spicy..)