If you have small children, don't go to the Chedi, even that it is the hotel I would highly recommend.
Childrenfriendly on the beach is the InterContinental or the Shangri La, but the Shangri-La is a hotel complex away from the rest of the city, but great to relax and for a weekend. Not too far from the souq and lots of activities.
If you need more info, mail me, I have been living in Oman for 8 years