DVD problem

ok here is the situation if you can help me out.

my computer hard drive (1 of 2) failed and I sent it to a friend who installed a new one.

but when I got it back the DVD doesnt work.

I thought maybe I needed to re-install a driver if the driver had been on the failed hard drive.

but when I go in to have Windows automatically search for the driver, the light on the old 3 1/2 inch drive lights up, but the DVD light doesnt.

so I need to figure out how to get this right.

any hardware geniuses out there who can walk a newbie thru this would be appreciated.

thanks