If any file can not be deleted, then you can use the program LockHunter, which removes the active connections of other applications to that file, which allow you to change or delete file.
If you are a heavy twitter use, possibly with more then one account, than I suggest you to give Tweetdeck a try. You can arrange, schedule, monitor and manage your tweets with ease.
Samsung Kies is a program for transfering files between your Samsung mobile device and computer, syncronizing your Outlook contacts and tasks and much more.