I upgraded from 2000 pro to XP pro. Looks like all my programs are intact (Needed to update my scanner , AV, and zone alarm to get everything peachy.)
You can uninstall messenger (supposedly) and a couple of other programs by unhiding them from the add/remove wizard.
Uninstall "Hidden" Windows Components
Apparently, Microsoft didn't want you to be able to remove useless garbage like Windows Messenger. It's installed by default, and it doesn't appear in the Add/Remove Program applet in Control Panel.
Thankfully, you can force the issue by editing the SYSOC.INF file, which is located in the C:\WINDOWS [or your Windows XP directory]\INF folder. Open it with Notepad.
Under the [Components] heading, you'll see a whole bunch of parameters for various Windows applets. Some of them contain the word "hide." Those particular programs, which include Windows Messenger (msmsgs), Terminal Server, Pinball, and others, are installed on your XP system, but their entries are hidden from and Add/Remove dialog.
To remove Windows Messenger, edit hide out of the line that reads
so that it looks like this:
Save the file, close it, and open the Add/Remove Program applet. Click on Windows Components button and you'll see Windows Messenger listed. Uncheck it and click Next to purge that silly program from your system.