It almost sounds like XP has crashed on you. Did you shut it down normally ie. Start>shutdown? If not that could be where your problem came from and you could have baked the OS. You may need to reinstall, Although there is not much info here to make an informed decision. What does it do when you select start windows normally? Can you insert the disk and begin a restore or recover?
Insert the windows xp disk and restart the computer. If it does not boot to the disk you may need to change the boot order in the BIOS to cd as first boot device. Once you have booted to the disk you can try to run repair to salvage what you have, if that does not work or it tells you there is no OS available to repair then you are going to have to do a full reinstall of the OS. If there is data on the hard drives you must recover you MIGHT be able to get some of it from the recovery console, otherwise you may have to pay someone to recover the data if you did not have any of it backed up elsewhere. I hope you have been backing things up!