Nope I dont hink so... reformaT? when I remove my programs with the uninstaller (add/remove programs) I usually dont trust it, i go to c:/program Files, and delete the folder myself. the i go to search and look up the program (avast for example) and delete anything with the word AVAST in itl....
The first thing is to do is to exit and disable McAfee so it won't see anything start up along with Windows. You can't delete drivers in use. Once that is totally inactive you can start the process of manual deletion of the files and folders along with deleting the root keys seen in the registry. That's the awkward but manual way.
The installer for a program like Trend Micro's antivirus will detect and remove any previous antivirus program installed automatically as part of it's own installation. All you do is reboot the system there to see McAchooo fee get tossed and a "far superior" program go on with a far better uninstaller as well. Not complicated here. Use one to remove another.