I use this to silence XP a bit:
quieter.reg
CODE
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemStart\.Current]
@=""
[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemExit\.Current]
@=""
[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\WindowsLogoff\.Current]
@=""
[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\WindowsLogon\.Current]
@=""