I have also spent lots of time with my children in Bangkok. The Amari airport Hotel is the most convenient because its connected with the Airport, although I believe that the Amari Hotel did not give very good Airline discounts. I know that the Rama Gardens Airport Hotel, which is about a 10 minute ride from BKK does offer good Airline Rates. Just check with them too see if they can give you a good rate!

I think that BKK is getting a new airport soon, or BKK already moved it's operations from Don Guan Airport?

Regards,
AMS