Curious to see the opinions here. Let's vote!

My order:

1. Chapter 4: For Pigs the Bell Tolls
2. Chapter 6: 3 Days of Excess
3. Chapter 3: Of Glitz and Glory
4. Chapter 5: The Key to Pirates
5. Chapter 8: The Thousand-Year Door
6. Chapter 1: Castle and Dragon
7. Chapter 7: Mario Shoots the Moon
8. Chapter 2: The Great Boggly Tree

I played the game and really enjoyed it, but I can't remember individual chapters

I have no least to best but I sure as hell tell you the chapter that gave me the most trouble was the one with the 3 witches.

You mean the one in the twilight or the one in the three with the punies?

Damn it. It's been too long since I last played it, but I really enjoyed the one where you acquire the Yoshi teammate and fight in that arena. I'll have to revisit the game soon, but for now, my vote is for whichever chapter that is.

After a little googling, it's Chapters 2 and 4 I disliked the most.

Played this a few months ago. I feel like I enjoyed them all pretty equally, except for the excessive backtracking. I guess Chapter 3 was my favorite.

It's been a while since I've played it so I can't really say a favorite. Especially because the past two or three times I've played it I stopped at the Boggly Woods. This is one of my favorite games of all time but I think that chapter is just awful. The woods have a nice atmosphere I suppose and I like the characters introduced in it, but actually playing it is a chore and the reason I have only beaten the game once.

I really enjoyed Super Paper Mario on Wii. I really want to give this one a try.

OHH MY GOSH I LOVEEEEEE THIS GAME!! I just recently started playing this again and just beat chapter 3, which is probably my favorite. It's been a long time since I last played this game and I do remember loving the pirate chapter, but I don't think that beats chapter 3. There's just something about rising from the lowest rank to the top rank that's awesome.

I really enjoyed Keelhaul Key so chapter 5 gets my vote.