Find a KNOPPIX or other bootable CD. Test it on some other machine, set yours to boot from CD and if no-boot you'll want a new drive.
i have a sony vgn-fs740/w notebook running on windows xp home edition. my dvd drive does not recognize any disks. it tries to read any type of disk for around a min. and then stops witout any messages. i've tried all kinds of disks, cleaning the lens, uninstalling the drive, updates, system restore and total system recovery but it still will not load any disks including cds. when i go to my computer and click on the drive with a disk in, it appears empty. im in the army in iraq and this is my only form of relaxation so i dont want to have to mail it to sony