I can recommend Hotel Daphne, I stayed there in 2004 shortly after it opened, the staff were extremely helpful and the rooms are very nicely appointed.
Breakfast was included in the price and was fairly average, not as much variety as some other hotels I have stayed in Istanbul, but still sufficient.
They were also very nice sending me an email at Christmas time and on my birthday.
Very nice views. Theme: HotelComparison: about averagePhone: 90-212-225-4204Directions: Location is good, not far from Divan Yolu, and close enough to walk to the main attractions in Sultanahmet.