I use a Kodak Playsport at home, and a Flip Ultra at school(work).
Both are very easy to use with great pictures and sound.
Kodak edges it for me as its a little more robust, waterproof, cheaper and has slightly better video quality to my eyes. Though the sound is lower and it doesn’t look as … shiny! Flip is easier to transfer video to computer as the usb is built in. It’s also (slightly) easier for younger kids to use. But it is a bit ‘precious’ being shiny and expensive. Everyone will say Flip. They are very good – but give the Kodak a thought.
Kodak will do 1080p, 720p and 60fps @ 720p. Also has WVGA and a 5mp still. For under £100 its brilliant.