Hi There, I am arriving @ Pu Dong Airport at 2.40 PM and I will have approximately 5 hours (leaving at 10.15 PM for Vietnam) to see Shanghai.

As you have very limited transit duration, I suggest you take Maglev and then subway to East Nanjing Road to roam around the famous pedestrian and then walk to the Bund to enjoy the scenery. The Oriental Pearl TV Tower and Jinmao Tower at the bank of Huangpu River also deserve a visit.