Difference between Microsoft SQL-Server 2000 and Microsoft SQL-Server2005:
This question is one of the mostly asked question in an interview but let me tell you that in depth answer of this question could generate one complete book but let us see the difference here in brief.
Almost features of Microsoft SQL-Server 2000 are available in Microsoft SQL-Server 2005 with some improvement and enhancement along with some new feature. Let us see those in brief.
— GUI improvement (SSMS –SQL Server Management Studio)
— T-SQL enhancement
–DDL trigger support
Along with “Database Mirroring” as a high availability in Microsoft SQL Server 2005 there are old feature of SQL Server 2000 are also available like replication, clustering and log shipping but it was working for only SQL-Server 2000’s enterprise edition but in Microsoft SQL Server 2005, it is available for standard edition also.
Scalability was limited to 2GB and 4CPU in standard edition of Microsoft SQL Server 2000 but in Microsoft SQL Server 2005, it supports 4 CPU and no RAM limitation in standard edition.
As long as encryption concern there was no built in option available in Microsoft SQL Server 2000, you have to have third party tool and expertise to use that tool while in Microsoft SQL Server 2005 it comes up with inbuilt encryption support.
Apart from that, MS SQL Server 2005 comes up with BI reporting tool as known as “YUKON”.
Reference: Microsoft Site