Both hotels are very nice. North Chas isn't the nicest area, but the hotels are top notch. About a 10 min drive downtown, so there should be plenty for the family to do. My last two trips I have stayed in the HGI because of free high speed bandwidth. If I was on vacation with my family, I would probably lean more towards the ES, as I think there is a bit more to the hotel (lobby, restaurant, bar, etc) and free breakfast. Plat gets me free breakfast at the HGI too, but not sure if that would extend to the family.
Good luck. Chas is a fun place to visit.
Cheers
Dean