If you have an existing Microsoft® SQL Server™ version 6.x installation, select Yes, run the SQL Server Upgrade Wizard to run the wizard automatically after SQL Server Setup has installed SQL Server 7.0.
If you do not run the SQL Server Upgrade Wizard immediately after setup, you may run it later at your convenience.
Whether you run the SQL Server Upgrade Wizard immediately after setup or wait to run it at another time, read the documentation about upgrading from an earlier version of SQL Server and make preparations for the upgrade before you run SQL Server Setup.
Upgrading from an Earlier Version of SQL Server