I went to KK last Christmas and also lived in Magellan Hotal. You can choose the Magellan club room. It is a little bit expensive than the standard room, but the club room is much bigger than the standard room. And you can have snack time in every afternoon. It is free of charge for all snacks and drinks. You also can have the breakfast in the club. I saw some tourist they need to wait the seat for breakfast in the lobby cafe.
You can try the restaurants 雙天 and 海皇城. The taste is very nice and cheap. There is bakery on the top floor of Center Point. The 菠蘿包 is very very very good. I ate 2 pieces and my hobby ate 3. Remember, they close at about 6pm.
The bakery is at the top floor of Center Point that is the biggest mall in KK. You can ask the hotel where is the restaurants. You can tell them that is the Chinese restaurant for seafood. They should know it.
I do not remember the address la.
1st day: Took early flight to KK and arrived early afternoon. Had a free 2-hour city tour (comes with Wincastle package). Checked in Magellen Sutera Hotel later, rest and had dinner in hotel coffee shop.
2nd day: Sapi Island Hopping Tour, also free with the package. We had great fun as we fed fish while snorkeling, played parasailing, flyfish (something like banana boat). Returned to hotel in the afternoon. Swan in hotel swimming pool. Went to KK town for Hainan Chicken Rice dinner.
3rd day: White Water Rafting. Left hotel at 9 am, took around 1.5 hrs drive to starting point of the river then rafting for 2 hours. It's great and not dangerous as we wore safety life jacket throughtout the journey (I don't know swimming and my son was 7). Had simple buffet lunch at ending point then returned to hotel in the afternoon. Swam in hotel swimming pool. Went to KK town for Seafood dinner.
4th day: Sapi and Manukan Island Hopping Tour. Went again as we wanted to feed fish. Personally I think Sapi is better for young kids, it's smaller and the beach is closer to the pier. Although the beach of Manukan Island is bigger and more beautiful, you have to walk from the pier for 10-15 minutes. Returned to hotel in late afternoon. Went to KK town for Hainan Chicken Rice dinner again.
5th day: All day swimming in hotel and enjoying its facilities e.g. bowling. Checked out hotel at 5 pm (requested late check out when we arrived on the first day). Took 8 pm flight and arrived HK at 11 pm.
Try Shangri-La Rasa Ria Resort, they have kid's club, their own beach and other activities. Nice hotel, just renovated. You can check the website, many nice pictures there.
Which beach your friend was talking about? There is only a very small beach in Magellen Sutera Harbour Resort and nobody swims there. I believe you can always find 烏蠅 in the islands because there are trees and forest, just the same as other islands in Thailand.