AMFLEET,
I'm currently running a ceiling/shelf layout just like the one you're looking to build (see the link below for a video of mine). Regarding your first question, yes. It's probably going to be louder than a table layout. When I built mine, I used MDF for the shelf, Woodland Scenics foam roadbed and then Atlas Track ontop of that. The mistake I made was not adding a layer of Homasote or soundboard above the MDF. This coupled with the fact that I may have screwed my track down a bit too tight makes running my trains at 35 Scale MPH or faster really, really loud.
When my trains run at those speeds, it's ungodly loud. The sound travels through the walls and into the living room and kitchens. Having said that, if you ensure that your actual "shelf" is isolated from the vibrations from the trains/track, yours should end up being much more quiet.
See video below and good luck!
PS... I don't have any switches on my track so I can't help you out there. I wish I would have added some though.
