“Full Height Anamorphic” means that it is a 720×576 image that will be stretched to a 16:9 aspect ratio later on.
In After Effects you need to choose PAL D1/DV Widescreen in both the Preset and the Pixel Aspect Ratio when you make your new comp.
If you need to bring in any footage that is already anamorphic make sure to let AE know that it is anamorphic. i.e. click the clip in the project window and press cmd+f (or ctrl+f) if you are on a pc (I think).
And choose widescreen in the pixel aspect ratio drop down menu.
You can work in widescreen by toggling the Pixel Aspect Ratio Correction on in the bottom of the viewer.