thanks zuber!
just tried it and it's wonderful...
installs quickly, it even offers to download ffmpeg for you (to do the audio)
so you don't have to search for it and it installs and configures it all by itself
and it only takes a few minutes...
it puts a download link on each youtube page under the video
and pops up a menu showing all of them
and it lists them plainly so you know what everything is...
if there's one that's video only it'll tell you,
and when you click on it it'll download the audio too
and mix them together when it's done
and you don't have to do anything at all...
it'll also extract mp3 from all the videos all by itself...
flashgot will download the ones
that are both audio and video no problem
but on the list there's no way to tell
which ones are which...