Since you state -2V to +2V input and want a 0-4V output, you have to 
have an overall gain of 1, no matter how many op amps.
4V change on input, 4V change on output.

If you want the same direction (sign of gain), you are going to have to 
add another inverted gain stage?
If you are going to read it with a Pic, you can fix the inversion there?

I am assuming you want the input on the non-inverting side of an op amp 
for high impedance?

Keep going...
Mike
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