First the easy one. The difference between SQL Express and SQL Server is that SQL Express has limitiation on the size of database's you can attach to it (4GB) where a SQL Server database has a max size of about 1.2TB
All of your other questions I can not answer as I do not use the SQL Manager inside of Visual Studio as it provides limited functionality; I use SQL Server 2000 at work and I use SQL Server 2005 Express for my personal projects. In the latter of the two instances, I am connecting to the SQL Server 2000 Server in code and the MDF file isn't actually attached to my project in Visual Studio.
Imar or Peter may be able to better answer your other questions.
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Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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Technical Editor for:
Professional Search Engine Optimization with ASP.NET
http://www.wiley.com/WileyCDA/WileyT...470131470.html
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Why can't Programmers, program??
http://www.codinghorror.com/blog/archives/000781.html
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