Don't forget the Coptic Christian parts of Cairo. Many fascinating churches and thousands of years of history and older than anything Islamic. Incredible artwork as well. I really enjoyed that part of Cairo that not everyone sees. Make sure you take your 8 year old horseback riding around the pyramids!!

Have a great time!! If you get tired of Egyptian food, you can always eat at Chili's right on the Nile.

ps: the train ride to Luxor is about 10 hours, so you might want to fly down there and spend the night down there and come back the next day. Every street in Cairo has a tourist agency so you can give it a shot while you are there, no problem my friend!