I would like to create a 2D game with animated animals. But it seems like Irrlicht does not support the gif format as the program crashes when I tried it out.
Yes, have a look at the examples that come with the Irrlicht SDK. There's even one named 2dgraphics. And the (tech)demo also contains an animated portal (drawn in 3d, but using 2d techniques). Animated GIF is a pretty lousy format for gameplay (especially because it's just a set of images, there's no special feature which would make animated gifs advanced over any other format.
There is an official image animator... it's the texture animator that you can apply to billboards (or any scene node i suppose..).
Weng, I used this website to get the source images of a .gif seperated out into individual images and then used the texture animator to play the animation in irrlicht.
Non texture one? You mean like draw2DTexture instead of using a billboard?
Using a billboard is probably easier but if you don't want to then you could always just handle the animation yourself, it's not particularly hard, just update the texture to the next one in the chain every X milliseconds.