Creating a logon script?

I am a newbie to windows scripting. Can someone please show me how to write a script that will copy some files to the local pc when a person logs on. The setup I have is as follows. All the pcs are either xp or 2000. They are all on a domain (cw). My server is windows server 2003.

I need to write a logon script that copy's 2 files into 2 different folders and different locations, depending on the OS. Win XP or 2000. And to run it only if the files don't exist. So basically run one time. Where do I place the script on the server so it will run on everyone's pc when the first logon?


In XP:
copy \\warren1\warren\grc.dat "C:\Documents and Settings\All Users\Application Data\Symantec\Symantec AntiVirus Corporate Edition\7.5"
copy \\warren1\warren\*.cer "C:\Program Files\Symantec Antivirus\pki\roots"


In 2000:
Copy \\warren1\warren\grc.dat "C:\WINNT\Profiles\All Users\Application Data\Symantec\Norton AntiVuirus Corporate Edition\7.5"