Found this in another forum (thanks theocsummer ). It's a bit old, September 2005. From IGN:

The Top 25 Animated Movies of All-Time
We pick the best.
by IGN FilmForce

September 30, 2005 - Here at IGN FilmForce, we like to argue; not about who tracked mud through the kitchen, or which of the editors used all of the toilet paper in the men's room. We like to argue about movies… which is better than which and why. Unfortunately, after the umpteenth shouting match, the higher-ups decided it would be a whole lot cooler to put all of this arguing to some kind of positive use.

Therefore, we came up with an exhaustive plan: we will rate the Top 25 movies for 13 genres in 13 weeks. Starting today, we will roll out a new genre each Friday until we have covered the most important categories of movies, beginning with Animation!

The following editors took part in the endeavor, and their write-ups are indicated by the corresponding initials:

- Brian Linder- Senior Editor, IGN FilmForce: BL
- Brian Zoromski- Editor-in-Chief, IGN FilmForce: BZ
- Chris Carle- Entertainment Editorial Manager: CC
- Jeff Otto- Editor, IGN FilmForce: JO
- Steven Horn- Publisher, IGN Entertainment: SH
- Todd Gilchrist- Editor-in-Chief, IGN DVD: TG
I will put here the complete list but by now you have to go to the link and discover it by yourselves.

A similar old thread