Maximum PC

I wasn't thinking several times when I changed drives on my pc's and now I have at least 2 hard drives that still have program files, music etc on them but they are not in a pc. Any way to get music off them and de activate them so I can activate new pc. The easier the better
Thanks

The computer is what needs to be activated in order for iTunes to allow you to play it's media.

If you have media on those drives that were purchased from iTunes then simply importing them into iTunes should be enough. iTunes will recognize them as belonging to your account and will play the files without issue.

If the media you have on those drives were not purchased from iTunes and are free from other types of DRM then importing them will not be an issue either.

With iTunes you can activate up to 5 computers with the same account. If you are going to reinstall Windows on a machine that has been activated you should deactivate iTunes first so that you don't lose one of the 5 activations. If you didn't deactivate that machine then the only way to get those back is when you've used all 5 activations. You then have to go into iTunes account properties and tell it to deactivate ALL computers.