Also, is a full respirator mask necessary? I read that somewhere.

I think you're underestimating the time and the mess. Because that texture was sealed with probably several coats of paint, you will have paint chips as well - how old is the paint? If any of that paint was applied just back in the '70s, it may have lead in it. That's considered an EPA problem and you don't even want to go there. Also, remember that the texture material is used to smooth and even out the drywall seams before texturing even if your walls are all plaster. That's the reason no one sands it. Drywall sheets are smooth when applied but there are seam considerations designed to be evened out for a wall surface where the seams are not noticeable. That little sander may be great but you will have dust into every spot in your house unless you use sheets of plastic taped off to keep the dust out of the rest of the house. And, if you do get that texture down to a smooth finish, you will need to prime that and if using any kind of paint with any kind of sheen, you will see every little spot that you missed or went too lightly with the sander. That's why even painters will consider skim coating before trying to sand down texture - even if applying wall covering over the area. And, yes you will need a respirator, not just a dust mask, and protective glasses and gloves and preferably a coverall to cover your clothes and something for your hair too.

A couple of issues here. I agree with a lot of carolannr's comments. Sanding by hand it will be extremely difficult to make it absolutely smooth. I understand the temptation but it will create an unimaginable amount of airborne "dust". I don't think the shininess will be an issue because if you are going to paint it with chalkboard paint it is a flatter finish. I would recommend skim coating it, it is still a mess but a manageable one. I wish you the best!

Don't despair! You have a number of options for limiting the mess.

First off, I've never worked with chalkboard paint. But are you sure you need to skim coat or sand the wall? Perhaps one or two coats of primer will be enough to even out any drywall marks and texture? Or maybe just a couple of layers of the chalkboard paint? (Or some combination of layers of both the primer and the chalkboard?) Honestly, unless you're dealing with some strange issues, that might do it. There are no trophies for creating unnecessary work for yourself. It seems that, with wall finishing, you can easily make a mountain out of a molehill.

If you do decide on sanding down the paint or a skimcoat check out this youtube clip: It's a neat little trick by which you suck the dust out of your house by pointing a fan out the window.

If you feel that it's necessary to apply skimcoat, you should avail yourself of dustless drywall compound. It's a couple bucks more a 5 gallon pail at your local big box store and worth about ten times that amount. You also should google magic drywall trowel. There's a product and series of generics that allow you to easily and quickly apply a nice looking skimcoat. I had to skimcoat all of the ceilings in my entire condo because the previous owner applied a junky sand texture finish. So I swear by my friends, the magic trowel and dustless drywall compound.

Oh, and I have to second Carol's advice about lead paint. If there's a chance you have it, find a solution that doesn't involve sanding the paint.

Skim coat would give you the best results but you would still have to sand it prior to paint.

Just grab yourself a bottle of goof off pro strength remover, or a can of sprayable stripper and go. Post pictures when complete!

It's hard to believe that there isn't a thick self-leveling paint or primer that can cover knockdown or orange-peel. There's gotta be an easier way to get smooth interior walls than skim coating and sanding.

I will be installing a peel & stick backsplash in my kitchen. There is texture on the wall, so looking for options. I'm not a skilled DIYer. Any suggestions? Other than hiring a professional?