what is quickest way to go from pudong airport to hong chao rail station? Shuttle bus or Metro?

You must refer to Hongqiao Railway Station, right?
Of course the fastest way is to take a taxi. The duration is 40 to 50 mins if there is no traffic jam. The cab fare is around CNY 230 in the day time.
As for shuttle bus and subway, shuttle bus line 1 spends around an hour to get to Hongqiao Railway Station. But if there is traffic jam, subway is a faster choice. It takes around 90 mins on the way.
You can choose the way you like.