ok i might be wrog but i think that the hdd's have went bad or are going bad usually you can see a hdd weather is is formatted or not in the windows installer the only time i have hot seen them was when my hdd crapped out and i had to replace it on warrenty
first thinkg i would do is make shure bios reconizes the hdd(s)
if they do then you might try run the repair console on the win xp install cd and try and issue the commands "fixboot" and "fixmbr" (i think those are the commands /list shows all the comands i think) if that does not work then you are pretty much screwed i think but you could try one more thing. . . . a linux live cd called knoppix you can get it
here knoppix automatically reconizes volumes no matter the format. it can also fix MBRs (Main Boot Records) if i rember correctly
my hdd is a western digital and when it crapped out it would make a low pitch wine then click about five or six times and then repeat the process over and over again on the WD web sight i foud that if you dissconnected the IDE cable and it kept making noises it was bad so that is how i found out for shure. you may be able to find somethin on you hdd's manufacturs web sight to eliminate weather it crapped out
i dont know that it matters but the last owner may have played with the hdd's jumper settings u can try and check that but it is a long shot
sorry i could not be more help
jc01
ps i might check this thread once more tonight but i am getting extremly tired and it is almost 1AM where i live so i will be getting off soon