Aditionally, do this before disabling any services ::
Start -> Run -> type
Rundll32.exe advapi32.dll,ProcessIdleTasks
This performs exactly the same task as bootvis does.
Benchmarking on Windows XP
And about tweaking services,
please DO IT IN A SEPARATE HARDWARE PROFILE
System Properties -> Hardware -> Hardware Profiles -> select the default one present, click Copy, and give a name. Also make the new one your default boot profile, by moving it at the top of the list.
Then from services.msc, select the service you want to disable, click the Logon Tab, under Hardware profile, select the new profile and click disable.
Here's my tweaked services screen shots.
Note :-
1: Many services though you can see are set to automatic, yet they do not run cause ther are disabled in my hardware profile.
2: Bluesoleil Hid Service is only specific to users who use bluetooth (I use for the net)
3: NOD32 Kernel service only specific to those using NOD32
4: NVIDIA Display driver service can be disable safely even if you are using a NVIDIA GPU card, but it is required to apply any custom clock settings during Windows Startup.
5: Logical Disk Manager can also be disabled, if you use a 3rd part defragmenter. The service is also needed for proper RAID working.
6: DCOM server process launcher can be disabled, however you may frequently get a RPC server unavailable error in Windows. Then you have to start the service manually. Also softwares requiring the Windows Installer service will fail to start.
7:
The following settings of services, gives me no errors under Eventlog, and also does not hinder normal XP SP2 operatins. Users using custom service settings should see for errors under Eventlog for any errors.
8.
THE FOLLOWING SERVICES SHOULD NOT BE DISABLED AT ANY COST
i: Event Log.
ii: Plug And Play
iii: Protected Storage
iv: Remote Procedure Call (RPC)
v: Security Accounts Manager
vi: Windows Management Instrumentation
Windows Audio service may be disabled, but you
may get no sound even if you use a sound card.
Windows Theme service can be disabled, if you don't need any themes, or you are using a 3rd party app like WindowBlinds.