Want to erase and install & reinstall iTunes libraries and some documents

Question

My iMac G4 Flat Panel is 9gb shy of being totally full and performance really suffers as a result. I want to erase the drive and install Leopard (I just bought a new disk).
What is the best way(s)/procedures to backup my iTunes libraries and some documents so that I can reinstall them on the newly formatted drive?
After paying for the Leopard disk, I don't want to buy any other programs to do the backup. I have been backing up the drive to an external using Backup.

Answer 1

Steven,
Backup is a fine application, but it typically targets specific items to be backed up. Meaning, that it is not necessarily entirely comprehensive. At least not in the context of migrating from one installation to another.
One of the concepts present in OS X is the idea that everything that makes your account "yours," all of your data, settings, history, etc., is entirely contained within your HOME folder. By moving that HOME folder into any new installation, you essentially transplant your entire experience as a user into the new location. In many cases, this works so well that, if someone did it behind your back while "swapping" computers with you, you would never know the difference. That's how it works, in theory.
In practice, there are usually some minor things that pop up in such a transfer, but these are all minor in the extreme. One might end up with a "question mark" or two in one's Dock, resulting from the absence of a linked application in the new installation. The question mark can be removed, or the application in question can be installed, so these things are easy enough to fix.
Your situation is complicated somewhat by the fact that you want to "whittle down" what you restore to the new installation. The assumption I make, based on your posts, is that you have only the one account, and your single HOME folder contains enough data to consume most of your disk space. OK, you can handle this several ways...
You could cover all bases by making one complete backup of your HOME folder as it is now, then begin "whittling down" what you have now before wiping your drive and reinstalling. This would give you the opportunity to reduce your disk space consumption while still working within your HOME folder; testing what you do, as it were, and with the knowledge that your deletions are not irreversible. When you find the right balance between what you can delete and what you must keep, you can make an additional backup of your reduced HOME folder (provided you have enough space on your external drive).
Or, you could make a complete backup of your HOME folder, as it exists now, then go ahead and format/reinstall. You would then have to decide what you will move from the backup into your new account. Part of this process is knowing just where to place transferred items for everything to work properly. As far as simple files are concerned, it wouldn't make any difference where you place them. Items contained in libraries, however, might be quite complicated to move, unless you simply moved the entire libraries in question. In these cases, the libraries themselves must be transferred to the correct locations. It's not an insurmountable problem, but it does complicate matters a bit.
Finally, you could backup and restore the HOME folder as it currently exists. Typically, the process of formatting and reinstalling, then restoring user data, results in a more compact installation. Over time, any installation accrues some fragmented free space, and this effectively reduces the storage capacity of a volume. As much as or more than 10% of the size of the volume can be recovered this way. In any case, your new installation will be smaller than the old to some degree, even with all of your user data restored. Once you get to this point, you could begin reducing the amount of data you have stored, just as in option #1 above, and again safe in the knowledge that nothing you delete is irrecoverable.
rsync is powerful. While it is easy to use, it has many options and is therefore complex to learn. Its "man pages" might be considered daunting. I could provide a copy and paste command for you to run which would make a complete backup of your HOME folder, provided I knew the path to a destination. The exact name of your external drive, along with any nested folders therein you might want to use as a destination, would suffice.
If you want to read more about rsync yourself, open Terminal and type "man rsync," then press <RETURN>. The "man" application will scroll line by line by using the arrow keys, and page by page by pressing the spacebar. Press "q" to quit the man application.
Scott