For smilies in particular if you look at the vary top of the post edit window there is a box to disable smilies. This sadly does it for the entire post you are editing. I agree that it would be good to have as a block command that can be set around specific lines leaving smilies in other areas of the post unaffected.
Thanks for the help Saudorun, but I hadn't had time to try this until just now, and when I went to do it I realized that there is no such box on the page I'm using. I think this is because it's not a forum post, but a "Static Page" that I've been editing using the BBCode parsing.
You can see the page I'm referring to
here, which I created using the "Static Menu Items and Content" option on the Admin page. Unless anyone else has an idea, I'm just going to disable BBCode parsing and re-create the page in HTML.