For a test try this
Download this file http://www.1kyle.com/ACTCD.SYS
this driver supports just about every CD / CDRW / DVD ATAPI device on the planet
Make a DOS boot disk
change the AUTOEXEC .BAT to
loadhigh NWCDEX.EXE /D:MSCD001
If you are using an MS DOS disk rather than DR DOS then use MSCDEX instead of NWCDEX
Change the Config sys to
SHELL=A:\COMMAND.COM A:\ /E:512 /P
Now boot and see if your CD 's are recognized
If you are using MSCDEX ensure the driver name ( for mine it's MSCD001) is valid.
IF this works then your Windows system is hosed.
If it doesn't your hardware is faulty -- try seeing if the connections have come unstuck or the ribbbon is not properly fitted into the IDE slot on either the motherboard or the device.
(Little Tip -- for diagnosing CD / DVD hardware problems it's much easier in DOS than using 'Doze).