I found the best video on Nokia N810 can be converted using AVS Video Converter. Convert to AVI, and select the option Archos AV500/700 MPEG4 480x272. It worked Great for me. Will only play on the Nokia if MPlayer is installed. Any video I had tried before was so choppy. I had been Looking all over the place to find out what would work best and trying different types and finally found this.! Wanted to share it.