Have you ever tried un-installing via the Un-install option inside of your SWKOTOR2 folder?
Specifically, if you go through start>all programs>lucasarts>star wars kotor2>uninstall?
Add/remove programs is a fine way to remove your software, but I reserve it for higher level stuff than games. Usually, as with this game, software installs with an un-install option.
As RH noted, the steps you have gone thru are vague at best. More info given will serve you well in the future.