Halloween. Call me lame or insult me for being a furry (disclaimer: please don't), but no matter what anyone says, it's a perfect opportunity to fursuit.
Christmas. Same reason as above. I don't think I'm ever as happy as I am during Christmas. I used to always love Christmas so much more but it seems that it's been getting lonelier as I get older.. Even so, I still love it more than anything else.
I wanted to say Christmas because I love the season and the Christmas spirit, but Christmas always turns into a huge fight with my family and it always ruins it for me...