The option's not there on my browser. Very strange! The snowflakes were a pleasant surprise for about a minute, then rapidly became quite annoying while trying to read threads. I wish I could turn them off.
I see the normal skin as it is listed at the top of the list.
But as an FYI, not all the choices are visible in many instances because the drop-down menu gets hidden behind the row of partners at the bottom of the page.
I now have access to the normal theme and life is mundane once again I'm ok with funky themes so long as there is an easy way to turn them off for members that find them detrimental.