what type of Octopus card should i buy?

hi! we're visiting Hongkong in September 1-4. 2 adults and 2 kids (5 and 7). what type of card should i buy? we intend to visit Disneyland, Giant Buddha and Ocean park... and macau if possible. is there a card that would cater to all this areas including airport? your reply will be very much appreciated, thank you. :D