If you google "pudong airport buses", you'll find a few relevant pages. The only one I ever take is #2 because it's a straight shot (no traffic until the last 2 km or so) to Jing'an Temple.

I tried #5 to People's Square once, and will never repeat that mistake (it wasn't the end of the world, but in addition to making an intermediate stop in Lujiazui, it crosses the river in the most congested possible place).

Yes, there are a number of nice hotels in People's Square, plus you have the park, the museum, a large shopping mall, access to both Huaihai Lu and Nanjing Lu, etc, etc. My only beefs with it are that it lacks the neighborhood feel that I like most about Shanghai, and it's kind of annoying to walk around the area because of all of the pedestrian barriers and foot bridges.