Yes, drag and drop, cut and paste, copy and then delete, etc

As the other posters have said, create folders with meaningful names on the D: drive, and just put stuff there. You can have the same folder names on the C: and D: drive if that's what you want to do, that's fine. The drive letter (C: or D:) is part of the full path name of the file, so even if the folder name is the same, the full path will be different. Or you can just drag and drop full folders from the C: drive to the D: drive. You can also use cut and paste on files and folders, or copy to D: drive, then go and delete from C: drive, whatever makes you feel safest while you're doing it. I would keep programs on the C: drive, though, if possible, and data files can be on either drive.

If you organize it so that program files are all on the C: drive, and data files are only on the D: drive, then if you have to re-install your OS, it won't affect your data files, since it will only touch the C: drive. Although you should have your data files backed up, anyways *smile*, this makes it easier to do an OS re-installation.