I don't think it's that easy when using wordpress functions.
In my header.php I put
<div id="navmenu">
</div>
where displayMenu(1) works very similar to wp_list_pages.
In CSS, I have
#navmenu {font-family: Helvetica, Arial, sans-serif !important; font-size:20px;}
#navmenu {float:left;}
#navmenu {margin-bottom: 0px;}
#navmenu {display: block; }
...
The menu is displayed vertically, and I think it's because it's called once inside the div.
There are of course workarounds, like simply making a menu with hard-coded links, but this would be a hassle if the blog moves to another address, for example.
I'd like to know how to change this function or wp_list_pages to display in one line, horizontally.
I'd like to send you a link to the blog, if you don't mind. How do I do it?