My favorite Sims for a nice walk at all seasons are the Calas Galadhon Park Sims. I wrote about it already in summer.
4 Sims and the Christmas Pavilion are now covered with snow. You can go sledding on the hills, rez a horse sleigh or go and ice skating on the lake. The buildings are all decorated for Christmas. You find on the sims many beautiful places to dance and cuddle.
Christmas Pavilion: http://maps.secondlife.com/secondlife/BAY%20OF%20BALFALAS/39/80/4005