I certainly would prefer to achieve success through some sort of recovery process because then I wouldn't lose everything on my HDD and have to start again from the very beginning, which I believe would be necessary if I completely reinstalled XP.
It sounds to me like you need to put your existing HDD to one side, get another HDD, install it into your PC, then put an OS onto it (you might have to buy that - 2nd hand on ebay?), then add your existing HDD as a 2nd (data) drive, either externally (via a USB caddy or cheap USB - IDE connector) or internally, assuming that you have the wherewithal to do so (space, power, IDE cable, etc.).
That way you don't lose your data, but can access your PC.
SD