1 - that YouTube video and the SAAMI instructions are EXCELLENT! If you're new to guns and ammo they are a must read/watch.
2 - .44 Magnum, as noted above, is NOT for the new shooter. If your gun is a 629 it will function wonderfully well with .44 Special, recoil will be quite minimal and easy to handle, and you can safely learn what you need to learn without tiring or hurting your hands. You can shoot a box or two of .44 Special at a range session, maybe even more than that, and have no issues. You will NEVER shoot a full box of 50 rounds of .44 Magnum at one range session.
Let me digress - I am a certified Texas CHL instructor. At our range session for certification we were required to shoot revolvers and pistols, 50 rounds each. The young man next to me, a police officer from Central Texas, brought a .44 Magnum with him for the test and .44 Magnum ammunition. He was a very experienced shooter, a military veteran, and when I suggested that he was out of his mind he laughed. Fortunately for him, even though the requirement is a 90% on the shooting test, he was a good enough shooter to pass DESPITE the bleeding hands and blisters he had by the time we were done. He looked at me and allowed that he would never do that again. This time I laughed....
3 - .44 Special is extremely useful as a self defense load. In a Model 629, in a home defense situation, you are well served with .44 Specials in your gun. Believe me, it will be loud enough and crazy enough, if you're defending your home and family, without having to deal with the muzzle blast and recoil of .44 Magnum loads, never mind the over penetration that you risk. Fun note - in one movie or another, even the famed "Dirty Harry" admits he loads .44 Specials in his "most powerful handgun in the world". It's good advice.
4 - because that YouTube video is so good let me just note that there is little to no risk, if you pour those rounds out of your gun's cylinder, of them even hitting the floor but, if they do, you'll have to drop one dead straight onto a nail to have a possibility of the primer being ignited. We've all dropped rounds; it's not nearly as scary as you might think. Just learn to be careful and DO count the rounds and the cylinder holes/empty chambers - that's great advice, too.
5 - Assuming you have boxes and boxes of ammunition to store, don't worry about them. They won't go off by accident, they don't blow up if there is a fire, although some primers might cook off it's not like a fireworks factory explosion, and they last a really long time. keep them away from kiddies or anyone you don't trust - that's more important that how you store them. I live alone - I have ammunition kinda-sorta everywhere. Totally safe. It's neatly stored, not just scattered around, but that's because I don't want to step on rounds, fall, and break my neck! But that goes for anything you keep around the house.
***GRJ***