You will need to remove any planks that are damaged of course. Cut at center of joist, but make sure all boards are supported by at least 3 joists. If some are structurally good, but have some mold, use a product called Condrobium. http://www.concrobium.com/
Do not bother with bleach, it will not work very well on porous materials, plus the smell is not good.
Once you're confident all is OK, you can install plywood underlayment and then your laminate floor. The underlayment should be min. 3/8" if the planks are flat and sturdy, thicker would be better though. I recommend 1/2" or thicker if the added height doesn't bother anything.
Back to the origin of the mold. Is this something that just happened or was it covered many years ago? Is the Pergo damaged, did it get wet? Laminate products may contain nasty chemicals too, it's not real as you know.