Go to Settings/System Settings/USB and change it to MSC. That should make the Clip act like any other flash drive and make drag and drop simple. The other mode is MTP, which is meant to work with Windows Media Player and sometimes gets tangled with write protection and other weirdness–best avoided, IMHO.
If you click down the music list, onto a second page, you will see Folders and you should be able to find your music the same way as on your computer.
But like most newer mp3 players, the Clip also works via labels rather than folders.
The Album, Artist, etc. lists you see are not folders. They are databases built from the ID3 tags–the electronic labels in the files themselves. Album lists every album title found among the mp3s. Etc. It looks like your Metallica albums don’t have the Album field filled into the ID3 tag, or the Clip can’t read that field, so it’s finding Artist (Metallica) and Track Number and doing the best it can.
This can be fixed pretty easily if you just bear with the one-time explanation below.
Get the free program mp3tag. http://www.mp3tag.de/en/
When you install it let it add itself to context menus (an option while installing).
After it installs, open it and go to Tools/Options/Tags/Mpeg and under Write choose ID3v2.3 and ISO-8859-1. (ISO-8859-1 is how Windows displays English language text.) Make sure those options are saved.
Tagging is not particularly standardized, and that will save tags the way the Clip likes them.
Right-click on an album and look at the tags. Click on the Filename header to put them in order–since those seem to be working–and then fill in the other fields correctly. You can label the whole album at once by highlighting everything and putting Artist, Album, etc. in the box on the left. Obviously make sure Album is in the Album field.
MP3 tag also has other nifty functions. One is Tools/Autonumbering Wizard. Make sure the files are in playing order, top to bottom, and choose the Leading Zeroes option. If an album has more than 10 tracks and they are labeled, 1, 2, 3, etc., the Clip will play 1, 11, 12, 13, before 2. Leading Zeroes fixes that.
Under Convert you can convert your filenames into tags. It’s pretty obvious how it works, each field is shown by %Artist%, etc. So in the Convert box you could type %Track% - %Title% and will fill them in from your filenames. That might be your easiest option, but mp3tag is very flexible and you should figure something out.
It’s best to take problem files off the Clip, fix them on the computer and send them back. You might just want to format it and start again. If you haven’t freshly formatted the whole unit, you can delete MTABLE.SYS from the Clip–that’s the database from the ID3 tags–and when you unplug it will make a new MTABLE.SYS from your new tags.
Going forward, it takes about 5 seconds to make sure Artist and Album are consistent on the whole album and run the Auto-Numbering Wizard before you add the album to the Clip. Then you can seek…and destroy.