Now this is a post I can help with! As you can see in my avitar pic, I bring a couple kayaks with me. A water craft is by far the best way to explore as you get a perspective of your surroundings imposible to see by hiking or biking, although I do all that as well. What style of craft all depends on your personal expectations. I own everything from kayks to inflatable kayaks, rafts with frames, SUP, float tubes, fishing cat, ect, all manual devices, I'm not a motor head to any degree.
For weight and storage, an IK or Inflatable Kayak is by far the best choice. A simple pvc IK from a hardware store will suit you fine if you only use it a couple times a year. If you want to fish from the IK, I suggest finding an IK with a Nylon cover to prevent hooks deflating your fun.
Canoes are an old favorite, but size, weight, and stability are their downfall. They haul a bunch of gear and I have seen up to 8 people in a 14ft canoe, but thats asking for disaster. Kayaks are by far more stable as they lower your center of gravity and each paddle stoke gives you a brace on the craft unlike a single bladed canoe paddle can do.
The key to remember about kayaks is, short crafts are easy to manuever, but lack speed. The longer the cradft the more speed you get from A-B, but the less stable you are going to be standing still. I could spend 2 hrs posting on design, but my suggestion is, ask around when you are out and about. I have been in the paddle sports industry for years and can tell you, when you step into a shop, 99% of them are going to try and sell you what they have the most stock of and telling you its the best for you.
One other craft that is super impresive is a Stand Up Paddleboard (SUP) it is the fastest growing aspect of the industry and amazing fun. My 68 y/o father has one and loves it. http://www.donkeyflip.com/dfportal/N...9/Default.aspx
They are super stable, pretty fast, and most entry level ones are designed for the lowest commen denominator. I have one and use it as my lake fly fishing platform when I don't feel like sitting waste deep in my flaot tube or bringing out the bulky fishing cat! Here is a link to one that can be used as an SUP or, you take the T Handle off the paddle, add the second blade, and clip in the foam seat, and you have a sit on top kayak at your disposal, its truely the best of all worlds. Not to mention its made from durable plastic. Heres the link: