Oops! lost multi-boot to start WinXP Home

[JimC]

I was installing my new 80 GB WD drive into an ABIT VP6 that was originally WIn98SE, and later upgraded to Win XP Home. I had a 15 GB drive on one UDMA 100 channel and a second one, 30 GB, on separate cable to the second of the two UDMA 100 channels. Since I plan to upgrade to dual PIII soon, I decided to set up a dual boot with Windows 2000 Pro, installing both original drives on ONE UDMA 100 channel in master/slave configuration, and installing WIn2K to the new 80 GB drive on the other UDMA 100 channel. The original drives are NTFS, and I had Win 2K format the 80 GB drive to NTFS. It installed OK, and at first I had a functional dual-boot---could either start the old WinXP Home, or boot into Win2K. For the installation, I had to set the boot order to BOOT FROM CD-ROM drive. I started installing drivers to Win2K. after installing the XP/2K drivers for my GeFOrce 2, I rebooted. I went into BIOS and reset the boot order back to Floppy first, then HDD 0. The HPT BIOS settings had HDD 0 set as the boot drive (when multi-boot was working). When I restarted Win 2K, the Hercules drivers were not successfully installed, even though they were for either Win2K or Win XP. I shut down, and attempted to boot back into WinXP, to go to NVIDIA to search for another driver. However, it found no bootable drive..."insert bootable disk..." So I started HPT 370 BIOS configuration again, tried selecting one of the other two disks as the boot disk. Then (too late!)I realized that I had left the HPT 370 driver disk in the floppy, DUH! No wonder it did not find an operating system! I set the boot disk back to HDD 0 in BIOS, and rebooted, with the floppy out this time. It would not boot back into XP, though. Now, when I select XP from the multi-boot screen, Win 2K attempts to start with the dashed lines at the bottom, then it does not find the correct files, and stops with error message to "press R to attempt to repair Win 2K"! I can still boot into Win
2K if I select Win2K from the multi-boot screen, but Win XP (with ALL of my programs) can no longer start. Apparently I screwed up the MBR? Is there any way I can get it straightened out? If the MBR can't be restored so that it points to the startup files for XP again, then can I unplug the UDMA channel with the Win2K/80 gig drive, and somehow use the XP Home upgrade disk to repair XP so it will run once again? But then, it is only the XP Home UPGRADE disk!
I am trying to get around buying XP PRO...I have already contributed too much to Bill gates' fortune!