This is such an easy tutorial - you can make buttons all day long and even use your ideas on color and strokes around the circle.
This is beginner tutorial. See other button tutorials that are more advanced is this one is too simple for you.
1. Create new file with 72 PPI and white background.
2. Select Elliptical Marquee tool. Place the cursor in the center of the image approximately.
3. Press Shift+Alt and draw perfect circle.
4. Select foreground and background color.
5. Select Gradient tool.
6. Drag from top left to bottom right.
[You must be registered and logged in to see this image.]7. With the image selected,
Select > Modify > Contract
8. Input the value 7.
[You must be registered and logged in to see this image.]9. Select > Feather
10. Input 3 as a feather value
11. Click the Gradient tool again and drag over the image from bottom right to top left.
12. Press Ctrl +D to deselect.
[You must be registered and logged in to see this image.]