This is a question that can start flame wars of near religious zeal.

The right answer is......whichever one works for you.

There are a couple of ditro's which are more newbie friendly than others, but the fact of the matter is......they are all essentially the same.

So now the question becomes which bells and whistles do you want and why? www.distrowatch.com has reviews of all the major distros. www.justlinux.com has had debates about 'which distro is best' more times than I can count.

To give you something concrete though, my recommendations for the total linux newbie:
Lycoris, Red Hat, or Mandrake.

I haven't tried all the ditros out there though.