You can use below script to rename SA account. Script will work with SQL Server 2005 and higer versions.

 ALTER LOGIN sa Disable;
ALTER LOGIN sa WITH NAME = [Jugal];


Check my new article on MSSQLTips

http://www.mssqltips.com/tip.asp?tip=2175

To limit the size of the SQL Server error log, the sp_cycle_errorlog system stored procedure can be issued to start a new error log. 

To recycle SQL Server Agent log you can execute sp_cycle_agent_errorlog system stored procedure.

http://www.mssqltips.com/tip.asp?tip=2164

Click on below link to download Denali

http://www.microsoft.com/sqlserver/en/us/product-info/future-editions.aspx