Originally Posted by
StckFigure
I tried to map to things like the Grand Palace and nearby temples, to Chinatown, to Chatuchak, and to the Jim Thompson house. Only the last one seemed "close", at least by transit... but it also seems like Google maps doesn't take the river options into account, nor does it seem inclined to connect BTS and MTR routes (but that could also just be my lack or orientation to the city). All of them have significantly shorter times listed for car, but I do assume those guesses are not taking into account traffic.
I suppose one good question for the Bangkok-familiar, without intending to get off-topic, is... which line is more useful for a standard first-time tourist, Sukhumvit or Silom? And anyway a difference of 2-3 minutes really isn't a big deal either way, so it may be a moot question.
Yeah this is kind of the first-time tourist dilemma in Bangkok, as the sights near the river can be a real hassle to get to from Sukhumvit (and yes, the traffic is absolutely awful most of the day).
If you want to spend time around or across the river (not just temples and Chinatown, but the malls, like Icon Siam), it's better to stay at the river. If you're going to stay near Sukhumvit, it's easier to get to the river by transit if you're on the Silom line. If you're going back and forth, the transfer between lines at Siam gets old fast.
For JJ market (Chatuchak), you can take MRT or BTS (Sukhumvit line). It's easier from Sukhumvit area.
I don't think most here would recommend St. Regis unless you have a specific reason to stay there. There are several Sukhumvit Marriotts that I'd recommend first.
You might also consider splitting your stay between Sukhumvit and the river if you'll be there for more than about four nights. Some of the best hotels in the city (and the world) are located on the river (Capella, FS, Siam, MO, Pen).