reboot into safe mode and log in as administrator. from there, you can change the ownership of the folders(by right clicking on them, properties and then one of the menus), then you can delete, move, etc. at will.

Intead of repeatedly switching hard drives, just put all the files in a zip, rar, or ace format, then email them to youself. Then re-download them from your email. thats alot easier, its what I do anyway, but whatever. Do what you will.