Edit Blender UI element how can i edit blender UI elements?
for example i want to change size of this button:



is it possible to do that? we can define or change UI's color easily by edit xml files. is there any way to change element's properties ???
The size of the icons is hardcoded in the c files to 16 pixels. You cannot resize it.

What you can do is to change is the DPI settings in the User Preferences in the System tab to have the whole UI in a dpi size that fits your needs. It's the first entry up left.