Here's performance tweak for Windows XP SP2

First go to the Registry, Start > Run > type regedit -or- regedt32

Then apply the following as necessary:

Disable the SP antivirus and firewall functions - and keep XP from nagging about it:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center]
"AntiVirusDisableNotify"=dword:00000001
"FirewallDisableNotify"=dword:00000001
; don't monitor firewall and antivirus
"AntiVirusOverride"=dword:00000001
"FirewallOverride"=dword:00000001

;Disable antivirus and firewall check at boot time

SP2 enables Auto Updates by default. This is good for you, but some folks disagree, so here is how to turn it off:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Curr entVersion\WindowsUpdate\Auto Update]
"AUOptions"=dword:00000001
;disable Auto Update
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Security Center]
"UpdatesDisableNotify"=dword:00000001
;Stop nagging about AU being turned off

How to turn off the SP2 firewall (if you must):

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Win dowsFirewall\DomainProfile]
"EnableFirewall"=dword:00000000
; turn off firewall policy for domain profile
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Win dowsFirewall\StandardProfile]
"EnableFirewall"=dword:00000000
;disable firewall policy for standard profile