WAV file

AIFF is like .Wav in every way except it supports tags. .Wav is not really a workable format for long term archiving because of the lack of tags. You can preserve the metadata for .wav files in iTunes by using the export library function and then reimporting the library file to the new installation. Keep the files in the same basic as the original but I have found the drive letter need not be exactly the same.

If EAC has a function that will tag .wav files with ID3 tags but I am not sure how universally supported this is.

For archiving, you want two things. You want a bit perfect copy of the sound file itself with no compression at all. But you also want complete and accurate metadata for each file so you actually have a file that you will be able to use with various applications for many years. .Wav just does not fit the bill.

I meant to say same basic directory structure as the original. Keep it simple, i.e., C:/iTunes/ or C:/documents/mymusic/iTunes or whatever.

I have found the best solution is to keep a drive that is totally separate from you system disc just for mass storage of files. On that disc, every few days or every week export your iTunes library to a file in the root of the drive to keep it updated. If something goes wrong on your system and you need to reformat or whatever, you have everything you need to restore your library, including the .wav files.