Well, I don't really have a preference at all, but if I wanted to play some great Mario games by seasons, I'd go with this list:
Spring - Yoshi's Island or the sequel for the DS, because they remind me of spring - especially the first world.
Summer - Mario Sunshine - Wait, I don't like that game that much, so I'd go with the latest Mario Kart, as a lot of the race tracks look like they're set in the middle of the year (more so than ever), and because its one thing the Mario characters do on vacation.
Fall - Luigi's Mansion, as it would go great with October and Halloween.
Winter - Hm, toughie. Maybe Dr Mario, since it reminds me of colds and sickness, which reminds me of the winter months.
Okay, so some of this was a stretch, but you get my picture. ;)