How to Uninstall STL from pc,?

This will be the 5th time trying to uninstall star trek legacy, I go into my computer, to uninstall/change program, click on stl and remove. But it sits at validating install :( it's been there for about 45 mins this time but same thing Happens, is there a way to get in the registry and change it myself? and just delete the folder ty for the help :)