The main problem its that i dont know how to save clips from Youtube to my Disk...i really hope someone had done that...
If you use
Firefox as your browser (you mean you don't already?) there are "Add Ons" available to do this. I use "
Download Helper". The resulting files are normally .flv format which requires something like
VLC media player to play them. These are all free open source programmes. I've just discovered that VLC has an inbuilt "screen shot capture" facility as well - Ctrl+Alt+S which is handy to take still frames out.