In addition, use of a fast shutter can produce a jerky effect, or strobing, on the playback. The range of shutter speeds should never affect your choice of camera as few people will ever require them. Focus - automatic on most camcorders but some have a manual switch. Sometimes the focus sensors don't know what to focus on and the focus motor whirs from one focus position and back again before it settles. So auto-focus is not always helpful.
Manual focus can be an advantage - although it is another thing to think about.
If you use it, zoom in close on the subject to focus and then pull back to the frame size you want. Only by going in close can you set accurate focus. At a wide angle setting things may look in focus but by the time you get in close the picture is blurred. Remember that in an extended zoom position it is harder to maintain sharp focus. It is advisable to get closer to the subject and use a wider angle lens setting.