Definitely check out the parade, holiday wishes, snow on Main street and the character dance parties at Ariel's Grotto and at Cosmic Rays. Last year the characters at Rays were better, but it's less crowded at Ariel's Grotto. (Last year Cinderella's step-sisters hosted the one by Ariel's Grotto, I hope not this year.) But it's a great opportunity for character interaction, especially for the little ones.
There are also refreshment stations throughout for hot cocoa, sugar cookies and apple slices. Woody, Bullseye and Jesse were at the Horseshoe Review refreshment area last year.
And there are Holiday themed characters at photo op spots but the lines are long.
If you're going to stay late, catch the 2nd parade and make use of the lull during the first parade.
And, if you get there before 7, catch the Castle Lighting ceremony, it's pretty cool!:xmas: