I received this from PCAdvisor when my Samsung Combo refused to play DVDs. It may help.
From Control Panel open System, select Hardware and click Device Manager.
Under IDE ATA/ATAPI controllers select the IDE channel on which the drive
is connected, click Advanced Settings, and then change the transfer mode
for that particular device to PIO Only. This will of course restrict the
data transfer speed compared to what would be possible using DMA, and it
will use a lot more CPU time, but if it makes things work that didn't
before you have to view it as a plus.
If you're having trouble using third-party CD-burning or DVD-player
applications try disabling Windows' built-in CD-burning support. To do
that, right-click the CD writer in My Computer, click Properties, select
the Recording tab and un-check "Enable CD recording on this drive".