PC won't boot, "unmountable_boot_volume" [XP], ideas?

OK.,
so about two days ago I went to boot up my laptop
when I was confronted by the Advanced Options menu
I selected the ''Last Known Good Config.'' option
and waited for the OS to startup.

a few seconds into the boot loading screen
the laptop restarted itself.
this time I selected Safe Mode.
same story
as this was a repeated problem I tapped the F8 key
until the Adv. menu came up again,
to find out what exactly the problem was
I decided to "disable automatic restart on system failure "

when the laptop came to crashing again a blue screen appeared
with white text headed UNMOUNTABLE_BOOT_VOLUME
this screen advised me to start in Safe mode
and/or remove any recently added
hardware/software
[though I can't access the files necessary for such nothing new has been added in over three weeks]

I contemplated taking the machine out to be fixed [only a year old it is still within the warranty] but thought I'd ask you guys and girls *spreads arms*
for help.

any would be appreciated.

thankyou.
Ky