Optical will not read

My DVD/CD combo unit just stopped reading disks of any kind I am running a Soyo KT400 Dragon Ultra mainboard with ATI X700 graphics card, an AMD athlon XP CPU, 1536m RAM. It began when I excessed a file I had taken off my wifes computer it has also stopped reading even when attempting to reformat the hard drive and now I can't get it back up. I have tried flashing BIOS and CMOS, I upgraded the BIOS, changed the IDE cable, I've switched to cable select, tried a different reader. I've been running this machine for about 2 years. My main game requires the disk in the drive and I'm having withdrawels please help!

 

Im assuming the bios is recognizing the drive and all is OK in the configuration stakes...(you gave us all specs accept for the optical).
Is it just a case of discs not being read?
If so does this occur when attempting to read both CD and DVD?