Icloud questions about contacts/photos and most recent IOS

Hey!

I have a few questions about Icloud because i am very scared that one day im going to break/lose my phone and not be able to acquire all my photos and contacts.

So i have a few questions for you

Q1. In the icloud settings window i have contacts little tab selected to save when doing backups...If i have that checked is that all i need to do to make sure my contacts are safe on Icloud?

A.

Q2. If i have a contact that i backed up to icloud, then i delete it, and back up the phone again, will the contact still be on icloud?

A.

Q3. To back up Photos/videos don't you have to go Settings > Icloud > Storage and Backup > Manage Storage > Click Iphones Name > Check the Camera Roll under backup options?

A.

Q4. If I don't have the most recent IOS. (I have 7.0.4) and i back photos and contacts up, then i get a new phone with most recent IOS, will i be able to retrieve the stuff on Icloud for sure?

A.

Q5. I feel the most important stuff for me would be saving photos and contacts, can you think of anything else i would need to make sure i saved?

A.

Q6. Can i be confident and feel safe if I've backed up my contacts with that little tab clicked to yes and my photos/videos with my camera roll option clicked to yes, even if I've backed up on an old IOS and need to retrieve it from a new IOS (on another phone) that i wont lose any of my important stuff?

Thanks again and i really hope I'm not missing anything. I'm just a bit nervous.