Clockwork MOD restore

Ok I have a few questions before a flash a new ROM on my phone. I've do a backup with clockwork mod. Does that backup contain all my info? (contacts, pictures, music, apps, and settings?
Also when I do a backup and copy the clockwork mod folder to my computer, if I want to restore from that backup do I put the whole clockwork mod folder onto the phone and flash that? I ask that because I noticed that inside the clockwork mod folder is a folder named backup, inside that folder is another folder with the date of the backup. I was wondering if you could just save the folder with the date on it onto the computer as the backup? This way if you have multiple back ups you don't get them confused.
Last I know with Icarus you have to partition you SD card. I was wondering if you wanted to restore your phone to before you put Icarus on it if the backup would revert your SD card back to normal?
Sorry for all the questions but I've been trying to get a direct answer to these questions before I flash any ROMS.
Thanks