your second part is much like a user access and right management and i believe spring security module is the best approach to achieve such goal Spring Security
This is one approach, however it also requires learning another framework on top of Struts.
In this type of application I would personally implement a UserInfo object to maintain in session with an account type field for basing conditional operations on. For instance, a super user account would simply have a boolean with a getter user.isSuperUser().
In doing this you can stick the UserInfo object in session and use struts tags to include different pages, for example:
<s:if test="%{#session.user.SuperUser}">
<s:include value="superUser.jsp" />
</s:if><s:else>
<s:include value="regularUser.jsp" />
</s:else>