My packard bell laptop has suddenly stopped playing cds or dvds, in fact it doesn't recognise that there is even a drive there. I haven't tried anything because i haven't got a clue about computers i'm afraid! Someone said it could be to do with I-tunes, which would make sense as thats the last thing i downloaded before it went caput. please help me, i'm at uni and its becoming problematic!!

Look at this post.
http://www.techspot.com/vb/showthread.php?t=29174

Try deleting upper and lower filters for the device.
http://support.microsoft.com/kb/314060/EN-US/