How to remove others avatar's when using the forum

So I have searched high and low but cant find the box to uncheck to remove other's avatar's from my view?? I can find the signature check box in my account settings but can't find the box to remove the avatar from view??

 

Is there anyway to reduce the size of the avatars when viewing a thread? They seem to be a more manageable size on search result screens but much larger on the thread response screens.

Thanks.