Yes, if you are using VB
then you should be looking for themes.vb
there rather than themes.cs.
As for your connection issue, it looks like you've got the wrong end of the stick with regard to 'instance names'. Looking at Lightwavers example here
connectionString="Data Source=localhost;Initial Catalog=ASPNETDB;Integrated Security=True"
The instance name you're referring to isn't 'LocalSqlServer' - this is just the name identifying the connection string in the web.config file and to the website - it's localhost, the particular named instance of SQL Server on your machine. If you install SQL Express and leave the settings at their defaults, the instance name is generally (local)\SQLExpress or localhost\SQLExpress. With SQL Server, it would be (local) or localhost. It's not the name of the actual service running which is what your MSSQLSERVER would seem to imply.
Assuming you installed SQL Standard on the same machine as VS Professional, you should be able to leave Lightwaver's example as is and have everything run fine. If not, you can check your database instane name easily by opening SQL Management Studio and looking for the 'Server Name' in the 'Connect to Server' dialog that pops up by default. That's the name that should repalce 'localhost'.
Hope that helps,
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