John,
I know little about most everything, but I know a lot about air rifles.
Some things you might want to consider...
1.) Where will you be shooting?
If you get a rifle that can push a pellet beyond the speed of sound, you will have a loud "crack" each time you fire.
Many folks opt for a pellet gun which can fire a heavier pellet at a slower speed, rather than a small light .177 cal.
2.) What will you be shooting?
Starlings and Tree Squirrels or, Crows and Cats and Coons?
3.) how much shooting will you be doing? .177 pellets are cheap as heck, .20 and .22 and .25. and .40 etc get spendy.
4.) how strong are you?
Some of the Spring Piston Air rifles take considerable strength to cock back, and are not suitable for youngsters because of that.
5.) What is your budget?
You can go from a red ryder to the moon here.
Id say if I had about $50 to spend on an air rifle, Crossman 760 or similar pneumatic.
A ton of fun, capable of light game and cans, accurate and cheap.
$100ish. Benjamin pneumatic.
$250 and up.... RWS
Remember though, as the pellet drops from supersonic to subsonic, it will start to tumble and go helter skelter.
I'd stick with a pneumatic to start, rather than a spring piston.
You can always graduate to a spring piston later on.... Id get a Benjamin in .177 cal...
Anything in a .177 you can also shoot a bb through too.
Many of the forums cater to the precharged pneumatic guys....
Those are really high end systems that you could hunt with... Pigs and coyotes etc.
I hope this helps a little.