Taskbar Reverts to Classic Look

[Bryan]

Every now and then my Windows taskbar reverts to the
Windows classic look when the computer starts up. I am
not sure why. If I try to change the theme back to
Windows XP I have even more problems -- computer does not
launch Explorer so it is basically just a beautiful
background with no functionality.

The only recourse is to immediately restart the computer,
using the hardware reset button, press F8, and select
Last Known Good Version........

Any ideas why this is happening and how to avoid it.

Thanks

Bryan