Simple questions, I think

So two questions - everytime I restart my computer my mac hd icon on my desktop moves out of place and, being the esthetic freak that I am, I have to move the annoying tag back to the right-hand corner it should be in. Anyone knows why it does this or what I can do to fix it?

Second question - I moved some songs from my windows computer to my mac and then open it up through Itunes. I'm assuming it makes duplicates of these songs (physical, rather than virtual so it's not just a shortcut) that's encoded through Itunes. I don't want to have two copies of my music so I just want to know if it'd be fine to delete the copies I brought in from my other computer or what?

All my music is imported to the iTunes library and deleted from the original location.

For your iTunes question, open iTunes and go to iTunes -> Preferences. Go under the "Advanced" area and the General Tab. If it has the option checked to "Copy files to iTunes Music folder when adding to library", then you will have a copy of each file stored in ~/Music/iTunes/iTunes Music where ~=your home folder. It would be safe to delete the originals on your other computer.

My Mac does not delete the original files after they are imported into the library. I must manually delete them. How do yours get copied and deleted, a script or plugin?