1、 Yes, taxi fare will be expensive. It may be about HKD250 from the airport to the hotel. Since you have totally 8 person, you may need two taxis. You can also take bus E21 from the airport and get off at Mong Kok Market, Argyle Street, then walk about several minutes to 968 Canton Road, you will get to the hotel.
2. Airport to Royal Plaza Hotel: Take bus E32 from the airport to CHEUNG ON BUS TERMINUS, then transfer to bus 44p to MONG KOK EAST RAILWAY STATION. The hotel is within walking distance from the station.
3. Royal Plaza hotel to Disneyland, You can take MTR from Mongkok East Station to Hung Hom, transfer to West Rail line to Nam Cheong, then take Tung Chung line to Sunny Bay. There you can take the Disneyland resort to get there.
4. From the hotel to Ocean Park, you can take MTR from Mongkok east to Hung Hom and transfer bus 171 from Cross Harbour Tunnel Toll Plaza to Aberdeen Tunnel Toll Plaza, then walk to Ocean Park. From Ocean Park to the Peak, take bus 6A from the park to Central. then transfer to bus 1 to the peak.
5. From the hotel to Avenue of Stars, take bus 2C from HEEP WOH PRIMARY SCHOOL to PENINSULA HOTEL, then transfer to MTR from MTR Mong Kok East Station - D to East Tsim Sha Tsui Station - J . Then walk to the Avenue of Stars.
From the hotel to Ngong Ping, the take MTR to Hung Hom, then transfer MTR to Nam Cheong. Then take Tung Chung Line and get off at Tung Chung. You can walk to the cable car termina to get to Ngong ping 360.