any gun you pick up, load, point in a safe direction, and squeeze the trigger and it goes bang. thats a good gun!! there are collecter grade guns out there, but im sure that your son/daughter is going to want to shoot it and shoot it often. Go to your local gun shops and just look around, the best advise you will pick up is in a gun shop, moms and pops gun shops are the best for that. watch the sales ads, Dicks, Gander Mt, Cabelas are almost always running sales on firearms and sometimes they are really cheap.
ive shot alot of different 243. savages, remmys. but i just like the action of Remmy bolt.
something that fits the size and ability of the child. There are a lot of bolts, or compacts. I started mine with a NEF superlight youth single shot. That's a VERY compact package, right around a yard stick long, and with 10 rounds on the butt stock and scope, still comes in way under 7 pounds.
My vote is for the Encore. It is a break action rifle. If the action is open the rifle is safe. it is that simple. Kids need to learn on a single shot. They need to learn to make one shot count. It is also a great choice because the stocks are not that expensive, and you can cut it down to the proper length in increments. Then just glue the pieces back on until the kid is big enough to handle a full size stock. Pretty simple.
I do not care much for your cartridge selection, unless you reload. A good handgun cartridge is much better for kids. Better killing power to 100 yards or so, less recoil, and much cheaper to shoot if shooting factory fodder. A 38 Special 357 magnum or a 44 magnum makes a fantastic choice. And ammo costs a bunch less. Tom.