How do I Choose Collision Area?

I'm trying this out and am making a Geometry Dash type game, but can't seem to figure out how to make it so if I collide into the side of the blocks that it would kill me. Instead it gets me stuck.

Thank you, I'll give that a try. I went in earlier and created a sprite bar that I overlayed on the blocks side, which when collided, destroys. It works perfect now, but I have to do it to every block, so I will try R0j0hound's way seems a lot better.Thank you!