Track and power

[sumor2000]

I am new to this and would like advice from the experts. I want to run two trains in opposite directions around my huge living room. I haven't measured specific yet but a rough guess is it is a 60' x 40' room. I am going to try to make the "shelf" around the room wide enough that in the future if I want I can add houses, stations, etc. I'm wondering what will be my best choice in track and power options? I'm guessing that O gauge is probably the best size? I did read a little bit of a couple posts about feeder and whether or not to solder. I'm more inclined not to solder just for the option to change design if I ever want to. Maybe I can get my wife to let me make holes in the walls and I make them go throughout my whole house. I'm sure that this post needs more information but I'm going to start with baby steps and do this right from the beginning. I look forward to hearing from you experienced modelers. Thanks in advance.

[DigitalGriffin]

Ahhh

For what you describe O scale seems to be the most popular.  As there is a WAF (Wife Acceptance Factor) involved and this isn't a kids room, you'll likely want something like a captains shelf similar to the one below.  They sell these parts at your local hardware store. 

That said there are plenty of O-scale track that has terminals on them for wires.   Due to the angle you won't be able to see the the second train track as much, and the first train track will need to be close to the edge.  Be sure to create a lip incase the train derails.  You don't want that landing on  your head.

You could use those craft based flat wooden houses that sold by the tons a few years back as a background decoration.