Dot, It is a matter of personal preference, for your size you could go with narrow beam width and still have room for sixty to seventy pounds of equipment. I designed and built one specifically for my daughter (5'5" and 139 lbs). Her kayak is 19"x17' with a displacement of 200 lbs. 200 minus her weight minus the boat weight (39 lbs) leaves her with room for 22 lbs of gear which would leave someone your weight with room for about 60 lbs of gear. Also you can go over the displacement with this boat an additional 60-70lbs and only sink the boat an additional 1". There's lots to choose from so do your homework before you start and as others have said, get as much paddle time in as you can first. There's no substitute for experience.

There's lots of pics at the link below. The "Restless Wind" album is of my daughter's yak.

Happy Building.

Charles.