This is old but I think it still works:
Expanded All Programs list text color is defined by:
Startmenu and Taskbar / Startmenu / Left hand side / Programs list [Text] tab, 1st "Unused (ignore)" state is Normal, 2nd "Unused (ignore)" state is MouseOver
Expanded All Programs list text font is defined by:
Startmenu and Taskbar / Startmenu / Left hand side / Item mouseover [Text] tab. Both Normal and Mouseover work.
Expanded All Programs list background color is defined by:
Startmenu and Taskbar / Startmenu / All programs / Background / [Extra settings] / All programs list background colour. If that hasn't been defined (i.e., "o/s default") it uses: System Colours / Button Face