Admin user - access issue

Hi
I have only one Admin user on my laptop with Vista Home edition. But still I
don't have access to certain issues. Can you please tell me how can I achieve
this? What settings will enable me to do those operations?

Some of the things I cannot do are:
1. When I start Real Player (even with Run as Admin option), I cannot update
it. It tells me that I am not an admin user and hence cannot update.
2. Cannot change the attributes of WINDOWS\system32 or any such folder.

Can you please tell me what I need to do to start using these features. I
have enabled UAC.