I'm assuming what you mean by the taskbar not going to the edge of the screen is that the template has a blunted edge that doesn't go all the way to the edge of the screen (the Diamond skin is the usual template unless you're on XP).  You can make the taskbar go all the way to the edge of the screen by designing it to occupy the entire canvas and using the margins to make it stretch all the way.

The start button can definitely be customized in Photoshop -- I usually make mine 70-75 pixels in length and then whatever is required for height, sometimes higher than the taskbar and then use the "glow" for whatever would extend beyond the bar.

Thanks for the warm welcome folks! I appreciate all of your replies and I will definitely be checking on those tutorials & links you provided. Oh, I was able to change my start button but I'm sure it was the long, hard way. The taskbar on the working template is what I was referring to. When in skin studio, the taskbar looks rounded on the ends and doesn't appear to stretch to both sides of the screen. I'm guessing this is the way it will look when I apply it as well. I'm running Windows7 Home Premium by the way & have Window Blinds 7.2. 

see ya around the forums....

Welcome back to the Community.