I want to make some of my emails totally unavailable. Would restore to a date prior to emails accomplish tha

Answer 1

No....a system restore does not effect your e-mails in any way.

Answer 2

No. But you can transfer all messages .
Open OE/Tools/options/Maintenance/store
( you may have to open explorer/tools/folder options/show hidden files )
Go to the store where the folders are stored. as *.dbx
Copy them where ever you want. Either you have to restore them or use special recovery programs.
If you don't want to retain delete them.
Now new Folders will be created in OE.

In Yahoo Mail delete them. No recovery possible.

Answer 3

No