Menu customization

Here is my website:

http://www.tillamookymca.org/

Is it possible to change the site page menu from the current format (with small page names running along the side of the home page) to larger “button-like” page names running across the page below the header?

I’m thinking of something in this vein:

http://ymcacw.org/

So, just five or six main page names running across the top, beneath the header, with drop-down pages.

I built this site for a client, and he likes most of the theme template very much, but wants this change, if possible.

Thanks!