Speaker Suitable for Baby/Children - Wall Mount

I use a pair of "the original" Duntech PCL-15, the larger of two wall-mount loudspeaker designs in the first line they exported to the U.S. When driven by my Aronov LS960I tube integrated amp, a similar, large space fills with great sound, including bass that emulates a small sub-woofer (don't ask me how it can hit real blues, and jazz electric bass notes, while hanging up on a wall, but it does). I bought these in the late 1980's when Audio magazine positively commented on them. These were from Australia, and according to the installing dealer even came with a genuine sheepskin for placement behind the speaker, to reduce wall vibrations.
I subsequently added floor-hugging Duntech Thor sub-woofers, affectionately(?) described by my tolerant family as "the coffins". These are surprisingly good self-powered sub-woofers for stereo, considering their antiquity, really fleshing out the sonic depths.
I think that if DIY'ers can really outdo Mr. Dunlavy's WL-1, then this talented, original Duntech designer apparently did not maintain his original perfectionistic approach when he migrated his wall-speaker concept to the later Dunlavy line of loudspeakers. But, I have never heard the WL-1, so don't personally know how it compares to his original Duntech.
If you see this older model for sale, it should work for you, but I have never encountered another owner. Anyone out there? We could start an exclusive wall-speaker club.
I have been in record/CD shop where regular box loudspeakers were mounted on wall, and in another shop from the ceiling, and the sound can be surprisingly good, but these were each smaller sized rooms, with less ambitious performance goals for the speakers.

I think wall mounting the kids is a great idea!

Kidding of course. I have a great three year old running around on whom I absolutely dote. Luckily, he's good about not fussing with any of my gear, though I am afraid he will sense my nervousness and do it just to get a reaction!

I think you're over-reacting by selling the system and getting everything off of the floor. But that's not my place to change your mind. 30x45 is a lot of volume indeed. I agree that the NAD probably won't have the power to push MMG-Ws to fill that large of a space. How far back will you be sitting from the speakers? More than 10-12 feet?

Another option - You *can* wall mount some of the larger speakers, like the Magnepan MMG, which reach down to 50Hz, give or take. That would be "more full range" than the MMG-Ws. But depending on your SPL requirements wall mounting the next speaker up in the line might be a better bet. the MG-12/QR. or faiing that, it's forerunners the MG-0.5/qr or MG-0.6/QR. The frames of those speakers are a little less flimsy than the MMG or MMG-W, and as such are better suited to higher SPL duty.

You might also consider something with higher sensitivity, like a wall mounted horn or maybe a wall mounted Gallo Acoustics speaker (but the Gallos will need a sub).

One other thing you might consider if taking your existing digital and analong front ends, build from DIY bookshelf speakers with one of the Fostex drivers (inexpensive), and switching to some inexpensive tube-based SET components. You may find your bedroom may be the only place you'll get peace and quiet to relax to the rig, plus it will be out the children's way completely. I have a friend doing just that with his first baby on the way.

I am in the same boat and I think you are right on track with getting everything out of the reach of little hands, here is what I have done:
I built a pair of very substantial shelves which I bolted into studs on the back wall with three 2.5" lag screws each. They support a pair of GMA Europas, which are very heavy and honestly a stretch for wall mounting, but great speakers that are worth the extra work. They like to be out in the room a bit, which wasn't possible, so I treated the back wall with ProFoam from Silentsource.com. Profoam is reasonably priced, has a fairly attractive appearance, and really made a difference in my room.
I installed my gear and music in a nearby closet (Consonance b2000x integrated and a Sony 222es SACD changer) and ran my cables under the floor. I have a 'powermid' (around $50) which allows me to use remote control while my gear is mounted in the closet.
The only real downside is a long cable run, but its well worth it to have my gear tucked safely away.
The results have been excellent, if not ideal, it takes up 0 sq. ft. of floor space and is safe from my toddler (and more importantly, my toddler is safe from it!).

What about the Blueroom Minipods? You could a multi-channel / ht system in 5 or more different bright colors. Watching the Teletubies might never be the same? They sell per each on Ebay at affordable prices.