What railway station should I take in Hangzhou to Shanghai?

Hi Im staying in Huachen Intl hotel, Pinghai Road, Shangcheng District and will go to shanghai to Grand
Mercure Shanghai Central , Meiyuan Road, Zhabei.
Which railway station should I take high speed rail and to arrive at Shanghai?
For the departure journey,Hangzhou Railway Station or East Railway station? And the arrival station in Shanghai,
Shanghai Hongqiao Railway Station ("上海虹桥 Shanghai) Hongqiao or Shanghai Railway Station ("上海 Shanghai")
I do not plan to book in advance. Will there be a problem to buy on the spot?
Many thanks