Simply deleting a directory completely removes almost no modern applications. Okay, maybe a handfull of small utilites. Doing so will not account for the hundreds of entries(files and registry items) that remain. Improperly deleting programs also leads to those annoying error messages stating that files missing. Likewise, individuals will complain that Windows slows down after time and the only way to remedy this is to reformat. Well, the problem is most likely caused by all that garbage that is leftover when removing programs. Anyway, to answer the original question. The ideal way to uninstall program is to use their built-in routine. Unfortunately, the script is always pathetically inadequate. Hence the proper method is to install a tracking program and monitor EACH individual install. Even this technique is not perfect, but I would consider everything else as being unacceptable.