Slowing Down Videos

What is the best you tube down-loader and 3rd party software for slowing down videos that you guys have found? Free would be preferred. Thanks…

-Matt

http://www.google.com/search?sourceid=chrome-instant&ie=UTF-8&q=fr#hl=en&expIds=17259,17311,27084&sugexp=ldymls&xhr=t&q=free+video+editing+software&cp=0&pf=p&sclient=psy&source=hp&aq=0&aqi=&aql=&oq=free+video&gs_rfai=&pbx=1&fp=a20cfd04ba3c5cf9

Hopefully that helps. I clicked on the first link, and I have heard great things about Imovie. The fifth option (Zwei-Stein) looks like quite an intense program as well.