"Invalid partition table" error when booting Windows XP.

I need some help diagnosing and fixing an "Invalid partition table" error when I try to boot my PC.

My troubles started last night when I tried to upgrade my Ubuntu installation to the latest version. I had Ubuntu running on a separate hard drive from my Windows XP installaton, so during the installation I had Ubuntu delete the partitions on the drive. The installation completed successfully, but it all went pear-shaped when I tried to reboot. Seems as though Grub messed up the drive mappings, and I was unable to boot into either Ubuntu or Windows from the Grub startup menu.

I messed around with the Grub config for a bit, but I couldn't get it going. So I decided to remove the Ubuntu drive from my PC, and then use the Windows recovery console to try and restore the normal Windows boot loader on the drive containing my Windows installation.

No luck. Nothing I tried would work. I've tried restoring ntldr and ntdetect.com from the CD. I've run fixboot and fixmbr with a number of different drive letters/partitions specified, and I've edited the boot.ini to change the partition I think Windows should be booting from.

Typing 'map' in the recovery console, gives me the following information:

C: \Device\Harddisk0\Partition1
H: \Device\Harddisk0\Partition2
D: \Device\Harddisk0\Partition3

C: is a small 56MB FAT16 partition which fdisk reports is the ACTIVE partition. Don't ask me why I have this... I've no idea. H: is an NTFS partition on which Windows is installed and contains ntldr, ntdetect.com and boot.ini. D: contains all my data.

My boot.ini file looks like this:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /fastdetect

I've tried specifiying Partition 1 and 2 as the default, but neither of those worked.

Anyone have any idea how I could fix this? Thanks in advance!