First thing to do after installing SQL Server Management Studio 2008
One of the strangest UI design decisions in Management Studio for SQL 2008 is that by default the Start Debugging button is right next to the Execute button as shown below
I myself have hit it by accident more times than I'd like to admit and I have seen many a demo (by MS staff as well) run into problems because of people hitting the Debug button instead of the Execute button! I think this is especially true for long time SQL users who have used Query Analyzer a lot as it looks exactly like the Execute button from QA. The good news is that you can simply remove it from the SQL Editor tool bar by clicking the Toolbar options button (as shown below) at the end of the SQL Editor toolbar, selecing Add or Remove buttons>SQL Editor and unchecking the Debug button. There is a debug toolbar you can use for debugging, it's just too annoying/dangerous having the Debug button right next to the Execute button.
