In my organisation we force 'classic' logon and theme onto Windows XP by
Group Policy, and there is no fading effect.
Right-clicking My Computer on your desktop, finding your way through
Properties onto the Advanced tab, then to the Performance settings;
you'll find a tab called 'Visual Effects'.
I personaly normally disable everything there, as for example I have
absolutely no need for a shadow under my mouse cursor.
I have not checked if these visual effects are available in the policy
editor in my Server 2003 environment, and I do not know your server
environment.