Modify the top.jsp file located at c:\subsonic\jetty\[version]\webapp\WEB-INF\jsp\. Add the following c:if statement around whatever button you want to hide from regular users. The log happens to be in help. This will only hide the button, they can still use the page if they know the link. If you want to change things on the help page you will need to recompile the source to make it be able to use the model.user.adminrole switch.
<c:if test="${model.user.adminRole}">
<td style="min-width:4em;padding-right:1.5em">
<a href="help.view?" target="main"><img src="<spring:theme code="helpImage"/>" title="${help}" alt="${help}"></a><br>
<a href="help.view?" target="main">${help}</a>
</td>
</c:if>