As to your other questions... There are no free watercraft at Disney, and you're not allowed to fish from the rentals. You can buy a bass excursion on a Nitro Boat or a Pontoon, it's pretty expensive, but fun. Around $250 for 3 hours.
As for what works, I always do good with topwater frogs/rats, senkos, magnum trick worms and roboworms on a drop shot.
Somebody else mentioned other places to fish, there is Turkey Lake right up Rt 4 (Bill Fredrick Park), with a park that rents boats, but you need to get there early because they only have a few. There are any number of small ponds along the the road I've seen people fishing at. Make sure you have a license because cops are everywhere.
There are also a ton of guides that will pick you up at your hotel too depending on what you want to spend. They seem to have pretty much the same prices within fifty bucks. I never used a guide down there, time being a factor with kids and the parks, so can't recommend a good one...