Topic How to defend your FE?
Take a look at my replay site, I've named all the matchups so you can find whatever you have trouble with, and I pretty much FE most of my games so it should have what you need.
I do 15 hatch 14 pool
This is where overlord sacraficing comes in handy. Throw an overlord at their base, count the factories/barracks/gateways/whatever else makes deadly stuff.
Suicide a Zergling at their front door, and see how many units shoot it. With that information you can guess when they will push out. Usually Terran moves out once they have 2-4 tanks and a nice pile of marines. So when you predict them to come along slow down the droning, make a couple of combat units.
If they expand, resume droning or if you think you can do it attempt to kill.
If they attack you, stop droning and make lots of Zerglings/roaches/whatever else you need
Day9 once said, choose either speedlings or roaches for early defense.
Speedlings beat red flame hellions, small numbers of marines and also they counter marauders.
Most of the time I take the risk to tech to lair while making speedlings if I feel that an incoming push is coming. At our level of play(high plat/low to mid diamond), most of our opponents regardless of age will push before spire. Before the completion of spire,we zergs tend to be kinda weak.Researching centrifugal hook helps.
Remember, the terran can choose to research either combat shield or stim pack. Most probably it will be stim pack.