These are the Aero style Dialog skins. They are based on the skin used in the original Aero UI. The alternate versions of the skin were created by colorizing the basic skin style. The effect created some skins that have a neon look around the edges and others that have a more subdued look.
The Aero Basic skin style is much like the one in the original Aero UI.
The Aero Colors skin styles are colorized versions of the Aero Basic skin. They have a neon look around the edges.
The Aero Gemstones skin styles are colorized versions of the Aero Basic skin. They have a subdued look around the edges.
Note: The above images are only sample styles and other variations are available to choose.