Hi christy,
The nearest metro station to Yuyuan Garden is the South Huangpi Road Station of Line 1(to the west of Yuyuan Garden), and the nearest to Jade Buddha Temple is the Hanzhong Road Station or Shanghai Railway Station of Line 1 (to the east of the temple).
In fact these two sights are not very convenient to reach by metro. Even the nearest metro station is half-an-hour's walk away. I think you can go there by bus.