I believe that all of your emails have the Sync to MSI checkbox checked when you are creating the emails. You should only have this value checked when you want to sync the email to Outlook\CRM.
To check click edit draft in any email and then open the edit settings window. Make sure the Publish to Marketo Sales Insight is checked or unchecked depending on your preference.
For each of your emails, you'll see an "Edit Settings" at the top. If you click "Publish to Marketo Sales Insight", that email will appear in the list of available templates in Outlook. Unfortunately, if these emails sit within a program, there's no way to rename these with a friendly name, and instead inherit the name of the program in Marketo (see this idea here: Sales-friendly names for Campaigns in Sales Insight ).