I am newbie to MSSQL Server and don’t have any knowledge about it.
i have below question.
I have added nine records with same value as show per below image in SQL Server 2005.
i Have not given any primary key to Table.
Now when i selecting one record or multiple record and hit the delete key it does not delete the records from table instead it gives me error.

You need to add a primary key to uniquely identify each record, otherwise the SQL server has no way of distinguishing the records, and therefore no way of knowing which one to delete, causing an error.