How do I update the SQL Server 2008 to include the studio?

Here is what I currently have on my machine:

I assume I am supposed to clidk on "SQL Server Installation Center"

From there I get this window:

and I assume I am supposed to click on the first item on the right side, "New SQL Server stand-alone installation or add features to an existing installation". Is this right?

When I do this, I am asked to "Browse For Folder" but every folder I have picked so far has been denied. What do I do?

I have even reinstalled everything from scratch off a network, and I still have this problem.