The start menu is controlled by the today theme.
www.pocketthemes.com and
www.pocketpcthemes.com have many themes to choose from. To change them you need to move the theme files to your PPC. You can put them in the My Documents folder in main memory or in the Windows folder. I suggest, however, that you create a My Documents folder on a storage card and place the files there. This will save you a lot of space.

The go to Start/Settings/Today and you will find the spot to change themes. Highlight the theme of your choice and tap the OK button. Your new theme should be brought up after a couple of seconds. Hope this helps.