Systems does not boot up!!!

Hi,
I have Windows XP sp2 on a P3 -899 MHz.
Recently it starts freezing for a while then comes up.
Then I thought may be there is a system crash
In the near future, I decided to change the Hard disk from my pc to another
PC. I opened up the computer and replaced the hard disk to the new computer
Then everything was working fine, except the CD-ROM
Then I tried to make my HDD as master and Cd-rom as slave
After that I booted up the system it comes to the profile page. When I
choose the profile as Win XP the it goes back to the boot process and
repeats. When I try to
start with the last known good config, it starts to load
then flashes a quick blue screen which doesn't stay on
long enough to make anything on it out, then the boot
process starts all over again. Same thing happens when
you try to start Windows normally. When you try to start
it in any of the safe modes, nothing happens and the boot
process starts all over again. Is have the restore CD's
but is there anything I can do before I take that drastic
step and lose everything?

please reply,adilsiv