We have a Bristol 32 with a swing keel. Our draft with the centerboard up is 3' 6". With the centerboard down we draw over 7'. Bristol 32s with a fixed keel draw 4' 7". On the positive side, we can navigate shallower water. A plus on the Chesapeake Bay. The weaknesses include having to raise and lower the centerboard via a cable running to the cockpit, a slightly slower boat, and more parts to care for (we're having our centerboard cable tube replaced now due to a failure in a previous repair).
My limited experience is that fin keels and wing keels are better for racing because they concentrate the ballast deeper in the water and closer to the center of the boat. I believe Sabres and Persons use fin keels and wing keels.
Shoal keels, as the name implies, provide a shallower draft to better navigate shoals. Most I've seen are full keels, running all the way to the stern. These keels tend to be better for cruising. Bristol 32 and Tayana 37 are good examples of full keels.
Take a walk around your local yacht clubs on a weekend and I'm sure many sailors would love to talk to you the strengths and weaknesses of their keels.
There's a pretty good little book 'A Field Guide To SAILBOATS' by Richard M. Sherwood (in it's second edition) that explains and illustrates different types of keels on different types of boats. Drawings of everything from dinghies to full blown cruisers and their specifications. Compact little book you can probably check out at the library.
Another one that should really be on any sailors book shelf is 'The Annapolis Book of Seamanship' by John Rousmaniere. Great reference.
I actually looked at the thread to see how keels could possibly be killing you! When the fixed keel becomes unfixed...THEN it might kill you. (which brings up encapsulated keels*). Until then, the thread title is a little non descript and over the top IMO. How about "Info on keel types"? BTW...If you think keels are confusing, wait until you discover the rest of the boat Oh...and you might want to stay from under the boat when it's on a Travel lift! You could be killed by a Keel (and the boat sitting on top of it) there for sure (or wish you had)!
*Encapsulated keels are molded into the boat and don't rely on bolts to to attach the keel to the boat. (The only relevant info in this whole rant!:laugher )