Before moving into our companies data into Office 365, the question must be asked, if we were to close out company, how do we get all our data out of Office 365 and backed up on optical disks?  

This includes files, sharepoint files and emails.  The files must be readable by any Windows computer system for legal purposes.

check the service descriptions for O365, and O365-dedicated: http://technet.microsoft.com/en-us/library/dn127064(v=office.14).aspx

for questions relating to the hosting aspects of O365, the O365 forums are probably best: http://community.office365.com/en-us/forums/default.aspx

Don,

Nice idea to post the question on O365 but I am unable to log in.

It seems that the O365 site does not recognise my Microsoft account, but Office 365 accounts only, and since we have not yet joined O365, I am unable to post to this forum.

Can you post my question on my behalf, please?

To slightly rephrase the question:

Before moving into our companies data into Office 365, the question must be asked, if we were to close out company, how do we get all our data out of Office 365 and backed up on optical disks?  

This includes files (1TB), SharePoint files (200GB) and emails (300GB).  The files must be readable by any Windows computer system for legal purposes.

What would be good is a weekly off line backup solution which would keep a "file-accessible" historic off line backup.  This way I would feel safer against issues where is someone had hacked our side and wiped our data.

I guess the "hacked our side and wiped our data" should not be an issue as Microsoft's backup would go back more than a week or month? and be able to restore the site ?

Would this solution that I found, work for a total of around 2TB of data ?

Your SharePoint sites is hosted online. If you want to back up your site, please refer these steps:
 1. Go to SharePoint site.
 2. Click Settings > Site Settings.
 3. Click Save site as template under Site Actions.
 4. Type a file name with descriptions. (Backup template is limited to 50MB, it's not recommend to save the site with Include Content enabled if files is more than 50MB)

If the content in your site is more than 50MB, you need to manually store them in your PC.

hmm, it seems the O365 mods have merged the two posts together:

If the files have been deleted for 7 months, they cannot be restored.

In SharePoint Online, the deleted files will be moved to the recycle bin. By default, items in the Recycle Bin are deleted automatically after 30 days. Regardless of whether an item is sent to the users Recycle Bin or to the Site Collection Recycle Bin, items are deleted automatically after that. For more detailed information, please refer to http://office.microsoft.com/en-us/sharepoint-help/manage-the-recycle-bin-of-a-sharepoint-site-collection-HA102772732.aspx?CTT=1.

In addition, you can use the following suggestions to backup the files and emails:

1. Use SkyDrive Pro to sync the library of SharePoint Online to save the documents to local hard disk and then backup them on optical disk. Please refer to the following article:
Sync your SkyDrive or other SharePoint libraries to your computer with SkyDrive Pro: http://office.microsoft.com/en-us/sharepoint-help/sync-your-skydrive-or-other-sharepoint-libraries-to-your-computer-with-skydrive-pro-HA103425074.aspx?CTT=1

2. Use Outlook to backup emails to PST file. You can connect to exchange online mailbox with Outlook and then save the email to Outlook Data File (.pst) to backup the email message. When you want to check the email, you can use Outlook to open the .pst file. Please refer to http://office.microsoft.com/en-us/outlook-help/export-items-to-an-outlook-data-file-pst-HA102809683.aspx?CTT=5&origin=HA102919679