<p>On the safari browser, the standard &lt;asp:Menu&gt; doesn't render well at all. How can this be fixed?</p>

You can use ControlAdapters to alter the rendering of server controls.
Here's an example:
http://www.pluralsight.com/community/blogs/fritz/archive/2007/03/27/46598.aspx
Though, in my opinion it might be equal amount of work to abandon the menu control for a pure css one (available on many sites).