Black Viper's Top 9 tweaks for a faster (and less annoying) Vista PC
 

The following is what I do directly after a clean install of Windows Vista . This does not mean that everything I do will work for you. Keeping that in mind, ensure you are fully aware of the risks of tweaking your system before doing so. Several of my performance tweaks "reduce" the default functionality of Windows and removes some built in security features. If security is a top priority for you or you are a new user to Vista, refrain from disabling any functionality noted as a security feature.

http://www.blackviper.com/WinVista/supertweaks.htm