Great idea starting him off with something with low recoil.
I tend to favor Marlin lever guns so right now I have a 1894C, a 336 in 35 Rem, and an 1895G.
The 1894 is a 38Spl/357. Nice little gun and cheap (relatively) to shoot. Weighs about 6 lb.
---> http://www.marlinfirearms.com/Firearms/1894centerfire/1894C.asp <---
In any case, good luck.
kind words appreciated .... I've been working with him for about a year .... first with BB's and now with 22LR .... he's come a long way and does really well .... below is a picture of him at our family shoot on Christmas Eve in Kentucky .... he was shooting the Ruger 10-22 we gave his father over 30 years ago ...