Personally, im not rreally a Zerg person. But I tried this start, and always win against Protoss, and not so well against Terran.
Immediatly, send all of your drones to mine. Don't build anything, and have your overlord scout. Once you reach 200 minerals (This will be extremely quick), build a spawning pool, and a drone when you have the minerals. Build 2 more drones until your cap is 9/9. Now build an overlord and try to save up 150 minerals.Now, start pumping zerglings, drones and hatcheries incase this fails. ( Don't forget the Extractor)
IF you've been scouting, you'll notice that most Protoss players will have 1 or 2 gateways up, and might have a zealot. If they have zealots. Do the following: Track along the side and get their probes. MAKE SURE while your doing this, you have resources pouring in, and are still building zerglings. Now, you should have taken care of maybe 4-8 probes before his zealots come. In this situation, use micro and try to keep him occupied, while constantly attacking his probes. Once you have backup, keep your zergling outside his base until you have about 20. Most players will be so preoccupied with your original 4-6 zerglings that they will just focus on chasing them. Now attack with all your zerglings and get rid of the zealots, probes, nexus in that order. Then just destroy his base.
It seems like this will take a long time, but you really dont even go over 3 minutes, and most of the time, less. ( This will be because of the waiting) You dont even have to build a hydralisk den UNLESS this fails. If so:
Well you failed. But, you still have to play don't you? So get about 8+ hatcheries, and try to tech as far up as you need. Keep upgrading and try and have all this set up by about 6 mins. The enemies will have ,most likely, DTs, zealots and dragoons.Try sending Zergling and hydralisks, or even just hydralisks. If you want to go air, send about 50 mutas with 20 hydras, along with some scourge.
Well, GL HF DD.