Also regarding keying lattice points, or chunks of points/vertices in general:
Select the points you want to animate
Create a Cluster for them (this makes the points selectable in the outliner etc.)
Animate the clusters instead of the actual point - this will give you greater control and overview of your scene.
Good luck.
Carsten Lind
Senior 3D Artist,
Maya Software Manager & Maya Instructor
LEGO Systems A/S