Making better art

Newbie & Debugging Questions
#1

My code is working fine
Just looking for suggestion

This is the result of a minigame of mine

The world is 640 by 640;
One circle is 64 by 64
See those circle
Why are they jagged
I made them in Photoshop
Ecliptical tool
Press Shift
Make perfect circle
Why am i still getting this

This is one circle btw

#2

Make the circles a higher resolution.

#3

Photoshop uses anti-aliasing, perhaps you tried to enlarge 64x64 circle by a scale factor, like said by HeroesGrave, make bigger circles and don’t enlarge them.

#4

made it 256 by 256
and this is the results

http://s10.postimg.org/iissq62zt/Resolution.png

Thanks guys