Big Fix is crap ware preinstalled on laptops and PC's it was quite popular although I haven't seen it in a awhile. How old is this PC? what make and model is it?
If the PC is running windows xp or windows vista/7 I would recommend you create you recovery disk, borrow/dl a copy of the OS and do a clean install. In most cases you can use the recovery disk to install applications for attached devices like webcams and fingerprint readers.