Hiya ben
(This is presuming you have already cleaned the lens)
The first thing to do is run full antivirus/spyware scans using something like AVG7, spybot search and destroy, Ad Aware etc. It's also worth going to
http://www.trendmicro.com/housecall and let it perform a full system scan.
If that doesn't work you can try a system restore (XP only).
start>all programs>system tools>system restore.
After that you can try re-installing the driver for your DVD player. If your using Windows XP go to:
start>right click on 'my computer'>select 'properties'>select 'hardware'>select 'device manager'.
Now scroll down until you find your DVD drive in the list. Double click on it and follow the instructions to uninstall the driver (ignore the warning). When you reboot your PC XP will reinstall the driver for your DVD drive.
If none of the above works you can try and find a firmware update for your DVD drive. You will need to go to the DVD drive manufacturer's website for this.
Hope this helps
