transfer my itunes to external

1) Is your old iTunes library on the iMac still working properly? If it is then say i"My old library on my iMac is working" because we need to know if there is any functioing library right now. If that one is working we will work with it.

What does it say at the very top, above the window that displays what's playing. A title bar if you like? On mine it says "iTunes" but in one of your pictures you showed it saying "iTunes backup".

Okay, go to iTunes > Apple > About iTunes. Which exact version does it have there? I am working with iTunes 7.5 open in front of me. There is a rectangular area at the top of my window. That displays the song name and status. Above that it just says "iTunes" on my computer. I don't want to know what is in the rectangle, I want to know what is at the very top. Unless your version of iTunes is radically different from all other versions I suspect that has not changed in since version 1.

Okay. That means the copy you put on the external was not the right one, or you re-named it on the external after copying and renaming that folder is a no-no.

In iTunes itself, go to preferences > Advanced and tell me what it says for preferences for keeping media organized and for copying iTunes to the media folder when adding to iTunes. If you are managing your music yourself as seems to be indicated by other things you have done then both should be unchecked. don't change them, just tell me.

Somewhere on your computer is a folder called "iTunes". Inside this folder is the "iTunes library" file and a few associated files, as well as an artwork folder. You showed this in your "iTunes backup" picture, but I am not clear if that was a copy of your "iTunes" folder that was dragged to the external and renamed, or if it was a folder called "itunes backup". The answer to that is important. Was the one you dragged before a folder called iTunes or was it called itunes backup?

Let's try this then. Rename that folder on the external back to iTunes. Hold down the option key while starting itunes on the old computer and select that folder, now properly renamed, as the location for the itunes library. It should start from it. If it does, check the integrity of songs inside it, especially ones that did not work earlier.

Edit: oh, did you move anything else around while renaming the folder or is everything else located where it is in the original folder on your computer?

No songs work? Not a single one (at least a representative sampling)?

Try dragging that original iTunes folder to that external again (you may need to re-name that un-renamed folder again). Do not change any preferences settings, do not rename anything, do not move any folders or files, just copy the whole thing. If you know a folder with music is located outside that library then tell me now before starting to copy, otherwise copy it. If you do copy it, try starting iTunes as before and see if it works this time.