Dear Shahzad727: In Ramadan and after Aug 14 there is expected to be considerable reduction in rush. However, we must not discount the fact that many who had planned to go to Naran my decide to go to Nathiagali because of the rains and the conditions of the roads etc after the recent weather conditions there. Nevertheless, since schools are open I think Nathiagali may be busy during weekends only. Having said that depending on the number of people in your family my first option would be Amore Hotel. It is in Dongagali and a standard room (which in fact is 5 star standard) would cost you Rs. 6000. Their deluxe room cost Rs. 13,000. I'm sure your family will really enjoy the plush interior decor of this hotel. It has nice views to depending on where the room is located.
My second option would be Summer Retreat which would cost you around Rs. 4000 (negotiable). And this is the place where I usally stay and would have stayed if it wasnt overbooked much in advance. This is the safest bet in the whole of Nathiagali. And I would not think twice in going for it.
The Raees Khana on the other hand in my opinion is something I would settle with when there is no other option available. In terms of location Raees Khana is very central and has a nice lawn and in terms of up keep the management could have maintained it better. It's close to the bazaar but still has its unique privacy and it isnt accessible by all. And it will not cost you that much...I paid Rs. 3000 (negotiated) during peak season so in Ramadan you shouldnt pay more than Rs. 1500-1800 max or even less depending on your haggling capabilities.
If money is no object then you should definitely go for Amore Hotel. I'm not sure which guest house you are refering to that Raheel has mentioned about. Anyway...
The choice is yours.