You can change the Start menu to any custom color you want, but that will, by default, change the Taskbar to the same color.

As you've probably heard by now, Windows 10 will see the illustrious return of the Start menu -- except it isn't quite the Start menu that you're used to from Windows 7 and Vista. In fact, it's better ...

The new Start menu overhauls the layout to address long-standing complaints. But you have options if you don't like it.