The Mega 2560 is an update to the Arduino Mega, which it replaces.
Are all the shield fits Arduino Mega or will I be limited in shield options because I choose the Mega (instead of the Uno for example)
better get the Arduino Mega coz it has more I/O connections
you mean that because the cables are spread all over the house over too long distances, I will have problems with the operation?
are those connections still can be used