1 way is to try what microsoft says(they put it there they should know how to remove it right?) (How to prevent Windows Messenger from running on a Windows XP-based computer)


Another way :
To remove MSN Messenger open your run box and copy/paste this:
RunDll32 advpack.dll,LaunchINFSection %windir%\INF\msmsgs.inf,BLC.Remove
Click OK, follow any instructions that may pop up, and and MSN Messenger will
uninstall! you should be rid of the little pain forever !
(Always easy to reload it if you decide you want it in the future.)


3rd way:
The following method works in Windows XP Professional, but
has not been tested on a system with SP1 installed. FYI, I've seen scripts that are
similar to this, but fail miserably, automatically deleting other much-needed
components! Better to do this slow and manually!

1. Exit MSN Messenger by right-clicking the MSN icon in the notification area, and selecting Exit.
2. Add the following registry entries, both with a DWORD value of 1: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Mes senger\Client\PreventRun
   HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Mes senger\Client\PreventAutoRun
3. Open a command prompt by clicking Start/Run, then typing "command" and clicking OK.
4. Uninstall MSN Messenger by typing "rundll32 advpack.dll,LaunchINFSection %systemRoot%\INF\msmsgs.inf,BLC.Remove"
5. Uninstall the leftover installation information file by typing "rundll32 setupapi,InstallHinfSection BLC.Remove 128 %systemRoot%\INF\msmsgs.inf"
6. Allow MSN Messenger to be displayed in the Add/Remove Windows Components dialog in the future (if it pops up again!) by typing "notepad.exe %systemRoot%\INF\sysoc.inf" and deleting the word "hide" from the line that starts with "msmsgs=". It MAY be possible to skip to this step directly and perform the uninstallation directly from the Add/Remove Windows Components dialog, but that method MAY leave unwanted components and has not been thoroughly tested.
7. Cross your fingers and reboot! You will probably get a message asking you to confirm the removal of some leftover files. Click OK.

Another way :

There Is a way to uninstall Messenger cleanly. I don't know if these steps apply for Home version.
1. Control PanelAdd Remove Programs click on "add remove windows components" on the left hand side.
In the box that pops up...scroll down to the bottom and highlight "windows messenger" then UNcheck the box.
2. Hit next and let the uninstall complete. (it's not a very obvious un-install) When it's, done make sure you
to RESTART WINDOWS! (the messenger icon will still be in the tray if you don't!)


Another way :

1. First, right click the Messenger icon in the system tray and click Exit.
2. Right click the Start button and click the Explore command to open the Windows Explorer.
3. In the Windows Explorer, expand the Program Files folder on the partition where your operating
system is installed (the partition that holds the WINDOWS directory) and right click the Messenger
folder and select Rename.
4. Rename the folder to MessengerDISABLED and press ENTER to commit the name change.
5. Restart the Computer. No more Windows Messenger



ANOTHER WAY

GRC*|*Shoot The Messenger**

Download and run our small (22 kbyte) "ShootTheMessenger.exe" utility. It will display the current
status of your system's Messenger Service. The button near the bottom of its window will allow
you to set the service to whichever state ? running or disabled ? that you desire.

If, for any reason, you should ever choose to re-enable the Windows Messenger Service, simply
re-run ShootTheMessenger to do so.

From Removing MSN Messenger from Windows XP (Updated) (Windows XP) - TACKtech Corp.
If you want to remove MSN Messenger from Windows XP and can't seem to find it in the Add/Remove Programs. You need to edit one file to have it displayed in Add/Remove Programs. There is a couple ways to uninstall MSN Messenger. One way is too run this command from Start | Run.

RunDll32 advpack.dll,LaunchINFSection %windir%\inf\msmsgs.inf,BLC.Remove


Another way
Search for sysoc.inf. It should be located in the C:\windows\inf\
Edit the file with notepad.




Remove the word hide. Save the changes




Open Add/Remove Software.




Click on Add/Remove Windows Components and you can remove MSN Messenger. There is two services to remove everything.




You can now remove both services. They have a bug with the check boxes but it still works.