How far is Kowloon from HK International Airport? Is it good to choose hotels situated in this area?

Well, Kowloon covers a large area. I can just tell you the general distance from HKIA is about 35km/22mi. In that area, the Yau Ma Tei, Tsim Sha Tsui and Mong Kok are the most bustling parts, with pretty convenient services and facilities. Therefore, you can find a hotel in these areas.