Which area of Cairo to stay in ?

Suggest booking. Com.. since you don't give a budget, pretty hard to give advice as good to some is shite to others... Hotel ismalia has some very nice newer rooms with views and a/c.... . AUstralia HOSTEL has some good budget backpacker rooms

The subway is brilliant in Cairo so don't worry about where you stay too much.

Yes I guess I wasn't very specific,looking for mid range comfy hotel somewhere in the 30-50 $/night.I would like a pleasant area that is convenient.
Thanks for the subway clue,I guess it will beat taking taxi's and buses.

Hey.. You can check the link below, it contains all the hotels in Cairo and u can filter to find the hotels that are best suited for u :)
http://eg.jeeran.com/en/cairo/search/?filters=subcats%3AHotels

Thanks MiraNah
I will look at it,but mainly I was looking for an area in which to stay to make the most of it.Atmosphere,restaurants,bars,cool vibe.

Given the places you want to visit, I think downtown (central Cairo)would be the best place to stay. Islamic Cairo would be within walking distance, same for the citadel. Old Cairo is easily reachable by metro from downtown.

It's not difficult to find a hotel in downtown, counts for different price classes

Personally I would stay away from downton. There was a bomb attack last week downtown (Italian consulate). I recommend to stay away from hotels near to all governement buildings, the ministry of foreign affairs, embassies etc. Look for a hotel in suburbs , far away from the downtown. Why not to check hotels in Heliopolis for instance...

Thanks for the suggestions,I am thinking to stay in Giza for a few days then move to Cairo.But I could stay in Giza for the whole duration and travel to Cairo to visit and return at night.I just wonder how long is the transport time.Maybe taxi to subway to the city ?

Actually, I'm staying in downtown right now and it's ok. But shiribaan's suggestion to stay away from governmental buildings is one to consider though.

Although Cairo is easily reachable by metro from Giza, I wouldn't take a metro to Giza at night. For a lone female western traveller it is not that safe. Giza is less developed than Cairo, with a lot of unlightened streets. A straight taxi drive would do I guess, and is probably faster than metro as well.

The suggestion of Australia Hostel is a good one.....down a side street but close to main street and only several minutes walk away from Tahir Square and metro. It is walkable from there to Islamic market area and also to train station.