If your os was installed using primary ide, then connecting it to a secondary won't let it boot and vise versa. Moreover if your partition table is corrupt! you need to repair your os using XP CD and droping to command console : you can try: >bootcfg /rebuild 'OR' >fixboot c: 'OR' the finally if you use >fixmbr c:, it can be a little dangerous if virus exists or a hardware fault. you must backup your data first. Good luck!
