In my opinion, Parklane is simply dangerous. It's simple, but the most dangerous mode of travel. Even if the driver is not falling asleep, the other drivers he has to contend with are out to kill you. Absolutely DO NOT use Parklane after dark, and only as a last resort during daylight hours.
I agree that the Hong Kong to Guangzhou train is the safest bet, but it takes a little effort from the Hong Kong Airport. Here's what I would do:
Airport Express towards the city, get off at Tsing Yi.
Transfer to Tung Chung Line (Gold) headed towards Hong Kong.
2nd stop Nam Cheong.
Transfer to West Rail Line (Purple) headed towards Hung Hom.
3rd stop (end of line) Hung Hom.
Take Hong Kong to Guangzhou train to Guangzhou Railway East Station.
China Hotel: Take Line 1 (Yellow) to Gongyuanqian Station.
Transfer to Line 2 (Light Blue) headed towards Jiahewanggang.
2nd Stop is Yuexiu Park (sounds like "jay-jew")
Garden Hotel: Take Line 1 (Yellow) to Yangi (3rd stop).
Transfer to Line 5 (Red) headed towards Jiaokou.
3rd stop is Taojin.
Having an Octopus Card for Hong Kong and a Yang Cheng Tong card for Guangzhou offers both convenience and discounts. Get the Octopus Card in the Hong Kong airport, and the Yang Cheng Tong card in the Guangzhou metro station.
Maps and other info for all 3 systems are readily available on the internet, all signage is dual language -- no trouble finding English signs, and the systems are safe, clean, and reliable.
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