only starting fine with windows cd in cd/dvd drive... hmm strange. Try to start with dvd in drive. Does it say something like "press any key to boot from dvd".? If you press any key it should start from dvd and Windows 7 setup appears. But you don't press any key, isn't it?
check the boot device priority in bios. Is it floppy, cd, harddisk? tell me what it is now