I/O device error

I have played CD's and DVD's on my lap top with no problem. Now I am taking a Human Anatomy and Physiology online class which has already started and 3 of the CD's will not open.

When I try to open them, I get "I/O device error"

I have tried to change the Primary and Secondary with the PIO or DMA but it will not help.

I have burned a copy of the CD's and tried them. they did not work either.

Can any one help?

Thanks, CDJ