 Sp2 Tweaks

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

Change some popup settings:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
;turn off IE popup blocker and return activeX handling to pre-SP2 setting for local system and current user
;1001 = 1 (prompt before download signed ActiveX)
;1004 = 1 (prompt before downloading unsigned ActiveX)
;1200 = 0 (prompt before download signed ActiveX)
;1809 = 3 (disable popup blocking)
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4]
"1001"=dword:00000001
"1004"=dword:00000001
"1200"=dword:00000000
"1809"=dword:00000003

Or you can disable Security Center altogether by disabling the wscsvc service.

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc]
"Start"=dword:00000004
;Disable Security Center