Depending on your budget, you may be able to get a hotel in Hong Kong with a kitchen/ette. Try using the search function at wotif.com and ticking the kitchen option - it comes up with a few alternatives both on the island and in Kowloon - including Langham Place and Harbour Plaza Metropolis. To entertain family, you would probably need a one-bedroom suite, since Hong Kong hotels are not known for their spaciousness.

Guangzhou is a two hour train ride from Hong Kong, is not really suitable if you want to entertain in Hong Kong.