...the problem with the magic wand tool is that 
it doesn't trim everything, thus leaving that 
pixelated "halo" you saw around your cels. I find 
the magic wand tool is more of a "companion" to 
trimming...if you want it to look clean you 
either use the tool and then trim, or trim and 
then use the tool to get rid of the rest.

I have to agree with Celtyrant, though...I'd 
print out the caps and then scan them...it looks 
as if the images of the cels and bgs were 
different sizes, and that when the cels were 
sized down a little oddly, making the cel lines 
pixellated.

It's a neat concept, but not quite right in 
execution. Great effort, though!

-Misha