Actually video is 29.97 for NTSC, I'd say go with 30 fps or 25 fps is acceptable for web/PAL. I'd also say go with MPEG 2 compression as used for VCD and that way you can pin it to VCD or DVD at a later date. Resolution is dependent on target if you're going for VCD/DVD then take a look at the MIR site for image and Pixel ratios. If for web/PC only consider 320x240 or 480x320. Resolution is going to be one of the biggest driver of size. Also consider (as mentioned) DivX or Sorrensen Spark compression.

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