Windows doesnt boot up and cdrom doesnt work

Ok im not exactly sure if anyone can help me but heres the situation.

I tried to reformat my computer awhile ago and instead ended up having two windows 2000 operating systems on my computer. I currently read something that showed how to delete one of the systems, which i did but when i rebooted a file was missing or "corrupt" and didnt allow windows to boot up. It asked for me to reinstall this file however it didnt prompt me anywhere. I tried to put in the windows 2000 cd and the boot cd and it doesnt read the cdrom.(changed boot sequence in the setup even.) Now im attempting at using dos disks, but its not working or i dont know what to do. If anyone has any idea or clues bout how to get my cdrom to work or how to format or "fdisk"? to work..please let me know. Thanks