2 iphones

Hello there!

I have an iphone 4/ipad 2 and my wife an iphone 4s/ipad 2.

We share 1 macbook, 2 apple tvs at home with i-tunes, face-time, always update iOS,...and want to

+ share music, videos, apps, even though different content per device.

+ need seperate e-mail accounts, notes, contacts, calenders per person/user?

How do we do this best? Do we need 2 accounts? Do we need to share one apple id?

What impact has iCloud on the above to be chosen strategy?

Please help!

Sebastian