So you get of your first train (to the change destination) then get of the train and just look at the boards for your train? Is they announcements when trains come in to and do trains normally wait 2-5 mins?
Sometimes there is an arrivals board showing the origin of each train, but this doesn't really matter to you, it's the departure time that bookings are made on. Some trains can wait for up to 15 minutes, but usually don't hang around for long at all.
How long does it normally take to read the boards and get to your platform?
Depends on the size of the station and the location of the board(s). National Rail Enquiries has a list of minimum interchange times, which is the amount of time the company that runs the station has deemed necessary to do this.
How do I change my name if it means that much to you lot, jeez!
I know it can be done, but I don't know how, sorry, you may have to PM a moderator.
What happens if my destination is mentioned on 2 boards, how do I know which one to go to?
If your booking restricts you to a specific train, compare it with the departure time on your reservation ticket, otherwise you can hop on any train as long as it's within the restriction code of your ticket. Sadly this is not published very openly, but is important for journeys in to London as off peak tickets to London, along with some other stations are restricted based on the time they are due to arrive at the destination. If in doubt, ask a member of this forum or at the information desk/ticket office if there is no information desk.