I think not all program from Windows XP is necessary for someone else, and they are get stucked on how to remove Messenger Windows XP from Program Files, here are the tutorials on how to disable Windows Messenger in Windows XP :
One thing that you need is registry editor, like the command below,
Step 1 :
Go to Start menu > Click -> Start -> Run
Step 2 :
Type in dialog windows : “regedit” (without quote) as like as picture below
and then click -> OK.
Step 3 :
You will see the main window of registry editor, go to the following path :
“HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrent VersionRun”
In the right column you will see the “MSMSGS” key.
Step 4 :
Just right click on the key with “MSMSGS” key and click -> Delete.
and Congratulation!, you have remove WIndows Messenger Successfully. When you re-start your computer you will not bored with Windows Messenger anymore. 
Good luck.
