If the fuse blows even with nothing plugged into it, there is likely to be a dead-short in the lighter outlet itself.
Check a local auto parts or junk yard for a replacement - should be pretty inexpensive.
The lighter itself is toast. There is a short inside so when you click it in too much current is drawn and it blows the fuse. The coil inside has a short.
The overdrive in the Windstar could have an internal problem, or the control from the overdrive button may not work. Run a check of computer codes to see if a problem shows up.
Could be the head gasket. Very common problem with this engine and model year Windstar.
You have a problem with your transmission. If it is only occasionally on - it could be just overheating. A dealer can retrieve the code to find out what the problem is.
Too much engine oil could be the problem.
Try this solution. http://www.leckemby.net/windstar/windstar01.html It seems that Windstars have a problem with the intake manifold.
If it blows while driving, I would replace the fuel pump. If it blows when trying to start, I would replace the starter.
There is two things what could be wrong with your lighter. One the wick in the lighter could be damp or you have bought a dull lighter.
Typically a relay or resistor. But could be a blower switch or blower motor problem.
Try it in another car. It is likely that the lighter socket is bad, but it could be the charger.
Condensor is overloading. Had the same problem last year.
The thermostat may be stuck open.