>Well yes Windows 2003 does't support .NET 4.5 so there's no getting around that.
>
>>About the switch you mentioned, is this a backward compatibility switch at the SQL Server level? If yes, what would be the advantages of running SQL Server 2012 if we ask it to run as it we would have installed SQL Server 2008?
>
>Well it's just that database. It's a compatibility mode so that the database can only use the features that are supported by 2008 not the 2012 features. If you need to deal with a DB that needs to run in multiple places (ie. your dev machine and a live server that are different versions) than this works. The engine is still running 2012 but only the 2008 features are available.

Thanks