In your Home folder, you’ll see a series of preset folders – Documents, Pictures, Music, Videos, etc. – put your stuff where it logically belongs using these folders. Load your music into iTunes and tell it “keep my music folder organized.” Load your pix into iPhoto and it will keep them locked up in the iPhoto Library in the Pictures folder. Feel free to make a set of subfolders inside Documents for logical groupings. You can set your Home folder to share in Parallels. And keep your Desktop clean!