Windows 7: Start Orb Dimensions?

Ok, I'm creating a new start orb in Photoshop. I've read the tutorials on this site but I need some more info. My Windows 7's screen DPI is set at 125% so I need an image that's 66 x 198. The only question I have is, what should the pixel dimensions of the actual button be and does it really matter? In ZaLiTH's tutorial he says to play with the dimensions, starting at 54 x 54. What does that mean? In his image size dialog box he's showing an image size of 45 x 45. I'm a little confused. BTW, I consider myself very skilled in PS. Here's my orb.

You will need the orb in 48x48 pixels . Though if you make the background in 54x162 pixels and the orb in 40x40 pixels , it will be the same when applied , coz the entire ui will be 125% enlarged in your computer, including the orb .

The orb looks great . No doubt that you are really skilled . Waiting to see the end result .

Thanks, Arc. So, the only real critical dimension is the ratio of the orb to the background, is that right? I mean, what would happen if I put a 48 x 48 orb into a 54 x 162 background?

Yes it is right . They are to be in proper ratio .

It will exceed the taskbar ... which is of 40 pixels height . So you will get only a part of the orb instead of the a complete circle .

Great info, Arc, thanks again.

You are welcome