Spyware, viruses, & security forum: Email phishing scam seems to have killed my computer

I have a Dell 3000 computer about 5 years old, 35GB hard drive, CD-rom, over 2 gb memory, running Windows XP with all of the service packs and other updates installed. I believe a fake "Hotmail Update notification" that I opened, which was a phishing scam, also contained a virus that wiped out the "boot.ini" and "HAL.DLL" files on my computer hard drive and made it impossible to boot my computer without re-installing Windows. IT GOT PAST 3 SEPARATE ANTI-VIRUS AND ANTI-MALWARE programs on my computer. They are AVAST! (updated minutes before the computer crashed), Malwarebytes Anti-Malware and Windows Security Essentials Anti-virus.The computer absolutely will not boot "normally". I can get to Safe mode, but nothing that is offered (except booting from a CD) works on this problem. It seems that these two files are the first two accessed by the computer when it boots and, of course, I can't get past them. I was able to use another computer and Windows XP-SP2 install disks to build a bootable CD using a program called BartPE. I can boot with this from my CD, but have limited access. I can copy some files, but cannot change anything in Windows and cannot get to the Windows Restore to try it. I can't find any "BOOT.INI" file, and tried copying HAL.DLL from the Windows/i386 file to the Windows/system32 file, but had no luck. It looks like I am facing either re-installing Windows (and losing all my files) or buying another hard drive and trying to transfer at least some of my files. I am buying another, larger hard drive, but if anyone has any ideas how else to get around this, I need to know ASAP. This computer is critical to my business..