I will offer my advise. While all the above posts are valid, the bit that is often overlooked is to get the kit that has the parts that YOU have interest in.
we had a cop who wanted to blink his Christmas Tree with the wig-wag lights line on a patrol car.
we have guys who want to water the garden....
or record atmospheric temperatures in hot air balloons as they rise....
or make robots.....
What YOU find useful is the best place to start.
as for the Kit, do look over the available kits and make sure that you get one that has the bits you think would be fun.
Go though the link that terryking228 posted in post #4
it has a lot of things that would be good to know about and will become useful as you play with things.
As a note, I have used his site for information on multiple occasions, well written for a person just trying to learn.
as for teaching an old dog.. you would be surprised how many of us are over 60 !