Are you planning to do an in-place upgrade? if so what I would do is install a version of 2000 on a different box and apply patches to pring it too the same software version. Then I restored all DB's and used sp_help_revlogin to migrate over all logins. I then did the upgrade and had our developers point some of there applications at this test environment to make sure everything was working ok. If that went well then I ran the upgrade advisor on the prod server. Note you want to run the advisor only nt the actual install which will run the advisor as well. then take a look at the report and verify there are no major issues. pay particular care to any that say before upgrade.