Simple question just about any one can answer I need a quick answer.

Question

Of course there are millions of iPod and iTunes users. and of course many of them want to back up their music, Reformat the same PC and pu the music they bought and legaly on Back onto the same PC.
I can't be the first person in iPod history to re-format.
So do I De-Authorize my PC "Before" or "After" I burn a Back up CD.

Answer 1

Well....You can Use iTunes for Backing up your Music, but I do not favor this mehtod.
It works fine for music files BUT: I prefer more control and completeness over my backup process. It is also very important to note that a large limitation of using iTunes to manage the backup is that the iTunes method does not create or maintain backups of the two meta-data files (iTunes Library.itl & iTunes Music Library.xml) where your Playlists, Ratings, Play Counts, etc. are stored. See: What are the iTunes Library files?
If you are heavily invested in your Library data (Playlists, Play Counts, Ratings, Last Played, Date Added, etc.), it is crucial that you also make and archive multiple backups of your ‘iTunes Library.itl’ file.
If your music is located under one common Folder (e.g.-‘iTunes’), then it is easiest to physically copy that folder and all its sub-folders in one simple process. It can be done quickly, and incrementally – several times a day, when necessary. In the case of any data loss, just re-copy your entire (or partial) music library back to wherever it was, placing it in the main Folder that the previous iTunes expected. Along with the ‘iTunes Library.itl’ metadata file, this completes a full ‘restore’ of your music to the time of your last backup.
Use of a backup software program will greatly help. It will allow you to easily perform incremental backups of only the files that have changed. WinXP has such a facility built-in. I use a free program called FileSync ( http://www.fileware.com ). There are many out there. Some use Zipped files or proprietary formats, others use standard file formats. I like FileSync as it uses normal file formats that can be viewed/managed via any Windows program or utility.
iTunes Files to Backup (anytime you make additions or changes to the Music or Library that you want to retain)
1) All music files in their current folder structure (usually located in and under the ‘iTunes Music’ folder)
2) The Library database file: ‘iTunes Library.itl’ located in the ‘iTunes’ folder
3) The Library XML file: ‘iTunes Music Library.xml’ located in the ‘iTunes’ folder
4) Any XML playlist files you created for Playlist retention
5) The two iTunes.pref files (optional)
-- C:\Documents and Settings\<your username>\Application Data\Apple Computer\iTunes\iTunes.pref
-- C:\Documents and Settings\<your username>\Local Settings\Application Data\Apple Computer Inc\iTunes.pref
6) The XML file of Ratings, Play Counts and Last Played attributes saved from the main Library and created by Otto’s SaveRatings script (also optional, but recommended):
“Download this: http://ottodestruct.com/itunes/SaveRatings.zip . It's a program, just run it like any other program. Run it on the machine where you're copying the info from BEFORE you move the files to the new machine. Click the "Save Ratings" button and it'll create a ratings.xml file. Now when you move the files, move the program and this file as well. Then after you make your new iTunes library, run it again and click the "Restore Ratings" button. Voila, all your information is back in the Library. Well, most of it anyway, it's not perfect. It'll tell you what songs it couldn't figure out though, and there's usually not very many.”
Here's a list of possible ways to copy your music files from your main iTunes computer to another storage medium for backup purposes.
1) Use an External Hard Drive to store the complete iTunes meta-data files and underlying Music Folder structure and songs from your main computer. They are quite cheap now, for their storage volume. This is my preferred main medium.
2) If you have Two Computers:
2a) Connect them through a router
2b) Connect them using a Direct (w/Mac) or Crossover (PC/PC) Ethernet cable (See: http://www.ifelix.co.uk/tech/3001.html)
2c) Connect them via a USB-to-USB Network Bridge. See: here as an example.
Copy the files and folders from one computer to the other. Use the second PC as your backup repository.
3) Burn several DVDs (at 4.7+ GBs each) with the music data files and store them safely. Re-writable ones are good for backup purposes (if your DVD drive can manage these).
4) Burn 6x more on CDs (at 700MB each) than in #3 above and store them safely in more space Re-writable ones are good for backup purposes (if your CD drive can manage these).
5) Use a larger USB Flash drive (1GB – 4+GBs) to store the files only if you have a small amount ripped music or have multiple and/or jumbo USB drives at your disposal that will fit your music library.
6) Use the Second Internal Hard Drive (if available) of your PC -- not optimum, as you really want to physically separate the storage of backups from the originals, but good as a tertiary storage device.
By keeping only one copy of your music (other than on the iPod), you are not truly 'backed-up' and are running a high risk of losing your music. Music files on just the iPod and the computer is not considered having any backup. If you cannot store your complete music files on the computer’s internal HD, then create and maintain at least two external sets (any multiple combinations of ExHDs, DVDs, CDs).
You need at least two full sets of your music, not including what is on the iPod:
-- One full set on the PC within iTunes (on internal HD or ExHD)
-- One full set on an separate external backup medium (CD/DVD/ExHD/other)
-- One (full or partial) set on the iPod
It is a good policy to backup all your important data. It is a very smart policy to back it up on more than one medium.
External hard drives now run less than $100 for 200-250GBs of storage. Very cheap backup insurance, indeed. See This Link