The speed of Santa

Several years back I was sent a forwarded email detailing the exact speed Santa travelled in a single night in order to deliver toys to every child in the world (minus those countries who do not celebrate Christmas, of course). The email then went into what would happen to the sleigh, reindeer, and Santa if they were your every day garden variety living beings. The email dealt with a lot of physics, if I’m remembering correctly. Any idea what would happen or where I could find it?

Here you go. With illustrations, no less.

I think this one is the most commonly forwarded one:

But this one seems more scholarly: