1. Your control panel (cPanel, Plesk, DirectAdmin etc.) login for your old hosting account.
2. Your FTP login of your account at your old host
3. Joomla, WordPress or other CMS admin login info if you are using one.
We will not be able to migrate your mail unless you are using cPanel at your old host. If you need to move over email accounts, it is easier to activate your mail accounts on our servers via cPanel before you make the DNS change.