Hi. If all of the water stained areas are getting replaced with new drywall you do not need a stain blocking primer on the new drywall. You will want to use a drywall sealer. Then prime it will the ceiling flat and then cut and roll the whole ceiling with the ceiling flat. You only will need a stain blocker if there are still water stain marks. If this is the case then yes use a stain blocking primer. PPG Gripper will work good. Zinsser 1-2-3 will be fine too. You just need to hit the water stained areas with the stain blocking primer. Then prime two coats of your top. Depending on home depot flat you may be able to just spot prime the areas you hit with the primer, feathing it out and then one full coat on the entire supper.

In a kitchen, I would prefer a more stain resistant ceiling paint, such as Behr Ultra Ceiling Paint. It is not uncommon in kitchen settings to accidentally spritz some catsup or coke, etc. onto the ceiling. Most ceiling paints are more concerned with drying dead flat than being washable or stain resistant. The Ultra will clean far better than the Behr 558 shown in the post above! the Ultra Ceiling Paint is so resistant that it actually can be used in moist bath/shower areas, a no-no for most flat paints.