I agree with Frank 100%. We used to do lots of video and never watched it. But our vacation photos scroll trough our computer desktop and we see them every day. I think almost everyone overestimates how interesting video clips will be in the future.
That said, however, there are times - like catching a street performer - when you just want a little bit of action in your vacation memories. I have heard plenty of people say good things about the Flip video, but it sounds to me like you are a person who hates redundancy - why have it if you aren't going to need it, right? So in that vein, I would suggest that you simply use the video function on your still camera. If you keep the clips short they don't take too much memory and the quality of the shots (at least in cameras less than 3 years old) are pretty good.
That's essentially what we have done for the last three trips and I wouldn't do it any other way. We have taken maybe 5000 photos which we adore and maybe a few dozen short video clips which we try to force ourselves to watch once a year or so.
By the way, HD is nice if you have an HD Tv at home and you use a tripod on vacation. If you don't have BOTH of those things, it is completely unneccessary. You would struggle to tell the difference between HD and standard.
