This is tough since I tend to like most of the daytime parades:
I was quite fond of the Parade of the Stars DL 45th anniversary parade (though I'm biased since I got to participate in it). I liked the Lion King celebration, Hercules and Mulan parades as well.
Eureka was a cool parade showing off the different CA regions. I especially like the SF scene with the guys dressed as the Golden Gate Bridge. It's nice to hear people say good things about BBB...I loved that one when it was at DCA (even if I embarassed my DH while dancing

)
As far a nighttime parades go, though I like Spectro, MSEP wins it for me.
I have never seen the Boo to You parade (and DL doesn't have a halloween parade), but I like the music!
For Christmastime...Christmas Fantasy (it's the only one I've seen, but I love the music! Very Merry Christmas Parade doesn't do it for me...sorry)