Marty,
Instead of rewriting the answer, read these replies.
There can be multiple reasons or a combination of reasons it "buffers".
https://discussions.apple.com/thread...art=0&tstart=0
As far as what resolution to film on, i.e. 720p vs 1080p? Use the 720p.
1. It takes up less room.
2. Faster to upload to your PC and youtube.
3. Unless a HD large TV screen is going to be used to watch them, no one else will be able to tell the difference when viewing on their PC from youtube.
Go to a video already posted and find one that has all the viewing choices and change them as your viewing. Chances are there will not be enough of a difference from 720p to 1080p for you to notice.
Watch this explanation. It is a little bit involved but let it play through.
Just use 720P and there will be plenty of detail. (IMHO)
http://www.youtube.com/watch?v=Z-JXfyvlPh0
This is one of mine shot on 720p. Both my GoPro's are set on that.
Go to full screen and change the viewing settings to see the difference. Granted 1080p is not there because I didn't use it.
It is not worth the space and time it takes to use 1080p for typical viewing.
http://www.youtube.com/watch?v=sxEgOMJDCQY
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