I think the combo of 2 & 4! The Nook Color is a great device especially when rooted. It's fantastic at magazines and books that rely on color photos. I also like it for night-time reading. You can share it with your son too.
Get him the T1, and he'll have his own ereader. There are some sales on the T1 right now (priced from $99-129). If he accidentally breaks it, then it's also cheaper to replace than the Nook Color.