Well TC, Boot is right in a general way but his idea of a boat is not necessarily everyones idea. He fishes the Delaware and similar places and his figures aren't far off for a more heavily built boat. If I were you I'd start tromping around and study the different construction types. At many of the areas that you fish at you just don't need much boat. For the areas you regularly fish a 12' - 16' open, floorless, aluminum hull is all you need and is where average fishermen have gotten their start since WWII. Most of them are plenty stable for average PA lakes (save Raystown, Paulpack, and Allegheny Res.
You see what my boat can do at 12'. If it had a transom there would be know end to where I'd take it. I've been Weakfishing in Chesapeake in 20kn winds, I've drifted the Delaware and now I fish a lake that is a mile wide in both directions. That little boat I posted above is a very stable boat like many others made over the years. Find one that is 20-25 yrs old and has a title on a minimal trailer, with or without a motor. It will not weigh much and will be a nice start. Personally I'd not shy away from no motor. That little trolling motor I have will push a rowboat for a day and a half on the half shot battery I have. Many a tranquil day/evening have I witnessed and there is more to come.
Look at your quest for a boat as a tutorial. Pay attention. Read about them. To learn about stability read the back issues of Small Boat Journal. Read the works of Phil Bolger, Reel Parker.
Look at this:
Chesapeake Marine Design offers a wide range of products and services in boat design and engineering including stock boat plans, custom yacht design services, computer aided design, and boatbuilding and yacht construction support.
www.cmdboats.com
After crawling around some of these site you'll know allot more about weight and balance and materials. You'll know more about what youre looking at when examining the potential of old boats.
These kayaks you have are also tying up your resources and when read you can cash them in. Once you have a boat you can buy a cover and store your gear and coolers in the boat and push it all into a storage facility.