Try these 3 different things:
2 - Download and run the Sony BMG Uninstaller. (This will remove any possible DRM installed when using Sony CDs)
3 - Search for these 2 files using Windows Explorer (afs.sys or afs2k.sys) and if found rename them by adding a 1 right before the .sys (ex. afs1.sys). These are old Oak Technologies files that have been found to conflict with cdrom.sys (the CD-ROM driver).
4 - Use the Dell Diagnostic CD Disc that came with your computer and run your dell diagnostic test on the cd drive, sometimes the hardware is just broken.