Nomura created the characters while under a contract with Disney. It's similar to how if you are paid to create a character for someone, they own the character.
As for the copyright notice... that refers to the Final Fantasy characters. Notice how the line stops at the year '2001' which is the year FFX was released. KH was released in both the US and Japan in 2002.
1990 = Final Fantasy III released, it's the first game that had Moogles.
1997 = Final Fantasy 7 released in US and Japan. That's the copyright notice for Cloud and co.
1999 = Final Fantasy 8 released. That accounts for Squall.
The notice on character designs in KH2 has all those dates (plus dates for 6, X-2 and Advent Children), but makes a point that it's for Final Fantasy characters.
Sorry for the long thingy, it's just something that caught my eye. It's a very nice rendition of the 100 Acre Wood book for walls, and I hope your baby does better than my nephew... ahahhaa.
I... uh... never got that far. ^^* Well, I mean in terms of Hundred Acre Wood. I've found that the only time I can muster patience for sidequests is in games like Digital Devil Saga and the like. But I could never beat Shiva and Vishnu in DDS2. ._.
I think it could work if you picked a more... serene presentation of Amateratsu. Not one where she's in "Time to kick some ninetailed fox @$$!" mode. Maybe when she's 'talking' with one of the thirteen Gods of the Celestial Brush.