Ultimate config file?

Hello,

i have really tried to understand this with dynamic image scaling, but my question is:

should i incorporate images for phones as iPhone 3gs is it worth it? and why isn’t iPhone 3gs in the emulator?

And what size should i put in background = display.newImageRect( “test.png”, x, y)

if the image i am using is:

original: 256px

@2x: 512px

@4x: 1024px

should i put 256px even if i don’t want to support that old device?

/Isak