Window XP Will Not Start

Hello,
I am having a serious problem with a Windows XP system. It is XP Pro SP3, it froze earlier today, and would not restart. So I tried booting into Safe mode, it will do this, 3 of 4 tries. After booting into Safe Mode I restart, no boot.
So I chose "Last Known Good" from the F8 Menu. But I can still l boot to Safe Mode.
So now I Booted Safe Mode, and did a System Restore. During Restore it restarted itself, and gave a message, on restart, that System Restore Failed. So I tried again with a Restore point from a Week ago - Same Thing....
So now I dug out my Windows XP SP3 Install Disk and tried to use it to get into Recovery Console. However the system restarts before the Installation Disc reaches the Install Menu.
So, any ideas?