OK, didn't know about your virus problems. If you haven't already done anything and are still worried about Itunes stuff. I don't use Itunes but I do use Spotify which might have a similar arrangement for storing data and playlists. I store the Spotify music files on a separate data partition as you do apparently. The playlists for mine are located in Users/myname/AppData/Roaming/Spotify/Accountname etc. so copying these to a safe location should mean that you can restore them if you have problems later.
My solution to backing up entails storing all data on a separate data partition with all data associated with programs - such as Spotify, BBC IPlayer etc - also stored here. I also have my Favorites on this partition too and these are incrementally backed-up regularly. I make images of the system partition regularly but since some data (like playlists) still exist on the system partition they will be returned to previous state thus probably erasing some items. The only solution, apart from having the complete user profile on the data partition is to regularly image after updating playlists or other programs or by copying this data and restoring afterwards. I don't think even Restore can cater for this but perhaps I'm wrong. I use Macrium Reflect for imaging and I am quite happy with it.