there is program called winconsole.exe, make a bootable disk from your XP install disk that does all the necessary thing that you need a boot disk to do, great for saving data when you can't get the repair disk to do what you need
System (XP SP3 Home Edition) repeatedly failed while trying to boot (blue screen momentarily displayed then it would loop and try to reboot again; I captured blue screen with a camera but it didn't help). Tried to boot from MS XP Home Edition SP2 install disk (note earlier SP version) and was able to go into repair section. Most options didn't work ... but ran CHKDSK and found one or more errors which evidently repaired them. I ran CHKDSK a second time and there were no detected errors. Rebooted the PC and it worked! Thanks!