Can I use Linodes DNS manager without running a Linode? I want to remove all of my Linodes, but use the DNS manager to point the MX Records to a different place (so the mail still continues to work). Is this possible, or will removing the Linode stop this?
You will need to keep at least one active Linode on the account for Linode's DNS hosting to remain in service. You will need to find a new DNS hosting provider if you would like to remove all of your Linodes.