The data file in Outlook 2000 is perfectly compatible with Outlook 2007.
However, the only way they would move "automatically" is if you were to
attempt an in place upgrade of Outlook, which is not recommended when you
are skipping several versions. It doesn't even work well if you're upgrading
just one version.
You would be far better off backing up your current Outlook data file,
installing Office 2007 clean, then using your previous data file with the
new installation. Detailed instructions are posted here daily.