You have an upgrade wizard that comes with sql server 2000 that allows you to upgrade from 6.5. There are a few preparation tasks as well - like making sure you have the correct service pack installed, backing up, verifying disk space needed, increasing tempdb ... I am going to link you to death - but this will help you prepare:
The following is a technet online seminar:
seminar
The following are upgrade articles:
article with upgrade document
problem article