If you first child will be 4 years old this September he would be in K2 for some schools and K1 for others, depending on the schools (some count by birth year [Jan-Dec] and some by school year [Sept-Aug]) My boy is born in Nov so i know how confusing this is in additional to the ready crazy admission process). For local schools you have the option of putting him in either.
1. Can he go to a KG school which also has primary and automatic transition?
YES-> HKIS/CIS/GSIS/CDNIS/AISHK/AIS/ISF/SIS/FIS/KCIS/YCIS/IMS/Anfield/ Kingston/Victoria...etc Many International schools' mass intake is at the Reception year, which is approx K2. Many private schools starts even earlier at K1 or PN. Some accepts application at birth, many a year before the start of school, but the competition for these schools IS quite fierce.
2. If no (which seems to be the answer) which KG school will ensure admission in a primary school (international school I guess)?
The answer is not 'no' above.
3. How do we decide on KG school apart from above? Which are some good options? I am not sure about the place I will stay, will decide the place basis school.
Woodlands, TutorTime, Greenfield, Sunshine House... they are all great kindergartens, and have branches on HK Island & around the city, depending on the school.
4. How easy / difficult to get admission in KG in a decent school
Given there is a great exodus into the through-train school by K2, the good schools with just kindergarten without primary are easier to get into by then.
5. When do I start looking at primary school for him
As soon as you can. Even if they don't allow for registation now you should look into it. For some, you can register now such as Anfield. Sorry i don't have a full list, others pls help.
6. Which schools are my best chances, will choose KG school near that.
HK lsland has the most number of Int'l school but also the greatest amount of competitions. The IS on the Kowloon side on the other hand seem to be a bit easier, especially if you are non-chinese. Schools such as AISHK and YCIS are located at Kowloon Tong, ICS is in FoTan-Shatin, and i believe a few schools near SaiKung. They are more spread out in comparison to the ones on HK island, which are mostly located on the south side or near around the peaks.
7. What is the thing about ESF - realised lot of parents want to put their kids in that school also they have both KG as well as primary.
Reasonably priced (as of now) with great IB score. Mandarin program is not a strong though. Also, starting 2014/15 school year for the K1 kids they no longer have interview priority into all ESF primary, the exception being RC & DC (they are the Private Inpendent ESF schools, which are newers and some claim the curriculum is not as strong).
Hope this helps. I hope my info are correct. Fellow parents please correct if i got any details wrong as i was only looking into the schools i was interested in / have heard of.