Blue Screen - Bad_System_Config_Info

I have a dell dimension 8400 running Windows XP Media Ctr Edition 2005. The other night it appeared to have a virus (although I'm running McAfee and up to date) and started throwing browser screens to sites I did not want to go to. I had to hold the power button to get the computer to shut down. Upon restarting I get a blue screen with the above Error message. I have been able to attach directly to the hard drive with a usb to SATA cable and backup all my data to an external drive. However nothing I try seems to work to get this machine back up. I've tried ultimate boot cd and it doesn't see the hard drive. I've tried an ERD disk and it doesn't find any version of windows anywhere. I have since tried booting from my windows xp cd to either repair or re-install the operating system and I now get the following error: intelide.sys caused an unexpected error (256) at line 5964 in d:\xpsprtm\base\boot\setup\setup.c . Short of buying a new computer, how can I get this one back up? I just new booting from the cd would at least let me re-install everything....

Thanks in advance. Terry