Excellent advice from Dabhand. The following may also help:
Be very nice to Santa - he can help you a lot or make your life a misery! Try and get ten minutes with him before the fun starts.
Switch off auto focus and ask Santa to hold his hand where the average kid's head will be. Focus on the hand.
Make sure you'll have enough depth of field so that, once the camera's set up, you never need to look at it again.
Get an off camera extension for the flash and hold it at arm's length above and to the side of the camera, on the side towards which the child is looking (if s/he's looking to
your left, hold the flash to your left).
Buy a new small notebook and at least two pencils. Write down each child's name as soon as you've taken the shot. You'll be nervous and flustered to begin with, so make that
three pencils.
Think up some simple patter to keep the child's attention on you, practice it before hand and don't be worried that it begins to sound like a chant. Small children won't notice and Father Christmas won't care.
Crouch down so your head is close to the camera and do your best to make eye contact with the kiddie. That way, the child will be looking at the lens and your flash should be at 45 degrees up and to the side.
Make sure the camera's set to post view the shots (just about the best feature of digital). Check that both sets of eyes are open and looking in the correct direction. If not, take it again.
I used to do a lot of 'smile please's and it can be quite rewarding in every sense, if you're fully prepared. If not, it can quickly turn into a nightmare.
