after sometime i decided to check out my windows registry, so i typed regedit and went in. and to my dismay, i could find several folders(or are what are they?) of programs i uninstalled some long time ago. prominently appearing among them were visual studios that i had installed some time back but later uninstalled. they include the visual studio c++ 2010, visual studio 2012 Express edition. and some other programs also, and i noticed that these folders are huge and I'm wondering if they are not slowing down my PC. so my question is, how do i deal with them safely, i haven't touched them yet..