The Winddancer is an older design. It's very, very stable. To me it
feels like paddling an ironing board. but that's just me. It has a very large
load capcity so it should easily float your 210 lbs. It is certainly not a
fast boat.
Yes you need a spray skirt. Surfing is good but, trust me, kayaking ain't
surfing unless you are surfing a kayak and even then I am sure it's different.
Please take some classes or contact a local kayak club and don't assume that
surfing has completely prepared you for sea kayaking.