Ironman
 Hello & Welcome to the Forum!
It sounds like you have a good handle on what you hope to accomplish with your around the room layout.
Screw your track down?  You might want to reconsider using screws, They will transmit the sound from the track to the wood which may act to amplify the sound.  You might want to consider hot glue or silicone sealer to attach your track to your shelf.
A buss system is handy to feed power from, especially with 200 feet of track.  After you get your track laid and you have your initial power feed to it, take your multi meter and go around the track checking for areas of power loss.  That is where you will want to add feeds to.
l would suggest sticking to lock on's to feed power to your track.
l hope this is of some help....
Happy Rails!
dave