Autopc.dkJust found this pretty nice article
its decribes many funny tweaks for xp and is worth to have a look at =)
examples:
Create a portable version of Windows XP
Disable annoying startup programs
Avoid having to re-activate Windows XP after reinstallation
Uncover **** passwords
and so on! 
While i was working at a computer store, there was ALOT of spyware removal and here is a quick quide to what i use to do, these little steps have worked most of the time
Its best if you scan while in Safe mode, but you can use it in normal boot, but if it dosnt really remove the spyware, then reboot in safe mode and try again
Oki
I use these apps:
Windows Defender, for protecting against spyware attack and it also have a good scanner
HiJackThis, This program shows all the stuff your computer starts up when windows is loading
If your computer isnt WGA approved, you cant install windows defender, or can you? yes you can..
There is an option to windows defender that does a silent install, witch means that it dosnt ask you any question doing install, to do this:
1) Goto Start -> Run
2) Type the full path to the directory where you downloaded windows defender to (e.g. C:\WindowsDefender.msi)
3) Before you click OK add this to the end of the text field: -qr so it looks like: “C:\WindowsDefender.msi -qr”
4) Click OK and wait for the installer to finish
Ok, after we installed Windows Defender, open it and and wait for it to update its database, there will be an green shield in the midle of app when its updated, i think its orange when you first start it up.
But before we start using defender we are gonna have a look at hijackthis
When you first start it up, it has a couple of options, like: “Do a system scan and save a logfile” or “Do a system scan only”
but click the button on the bottom “None of the above, just start the program”
and here is what you shall do:
1) Click “Scan” this will scan all the computers start up folders, reg entries and so on
Now you maybe think .. “holy sh*t there is alot for stuff listning there” but that my friend is what is slowing it down
2) Now here comes the tricky part, you have to de select all the things you dont know or dont trust, this can be hard if you dont “know your computer”, but if the file is in a folder that you know, e.g symantec, then it could be a product like Norton Antivirus or Internet Security.
3) Click “Fix selected” and wait until its done
Oki now we have decreased the boot time
Now run a quick scan with Windows Defender (is located in start)
The thing about Windows Defender is that it isnt located in the system tray, its only located in the system tray when it found some spyware og needs to update
When the scan is complete and it has solved the found problems (if any) then reboot and that should be it! 