Erland Sommarskog (8/18/2013)
It seems that the installation runs into problem because of the broken VS2008 installation. Although, there is no reason to enter an instance ID, since all you are installing is the tools. But I don't know the exact screens that SQLManagementStudio_x64/86_ENU.exe displays, and I cannot easily test it.
The installer mentioned that the master database is already present and that the instance Name contains illegal characters so I doubt the Problem is only with the Visual Studio Installation.
Your Suggestion of using SSMS 2012 should also be treated with caution. Although I haven't used it myself, I have had Problems administering SQL Server 2005 instances with SSMS 2008R2. I prefer if at all possible to use the appropriate SSMS for the database Version.