I just got a Dell Dimension 8400 about 6-7 months ago and it seems to be doing ok.  I am having a problem with the dvd burner (the one that came with the computer).  I haven't used it for a few months and before that hiatus it was working fine.  A few weeks ago I tried to use it and it had trouble opening.  The button won't open it most of the time and if it does work then it takes 20 seconds to kick in.  Also, when I insert a cd/dvd it doesn't recognize it.  It also opens up automatically when I turn my computer on (the button won't close it either, I have to close it manually).  I could understand a problem if I had been using it but I don't know what could be wrong since I haven't used it for a few months.  Any advice?  Thanks.