I could be wrong - but

There may be some significance in the entry that says "upgrade"

I know that it is just a description in the boot.ini file, however, it indicates to me that the XP install CD is not a full install?????

In which case the upgrade is relying on a previous install to take care of the boot.

The install on my dual boot - the boot.ini says only "Microsoft Windows XP Professional" - this was performed from an OEM WinXP Pro CD.

The WinXP Pro is on partiton(3) of rdisk(0) - my XP Home is on partition(1) of rdisk(0)

Did you try editing boot.ini?

(funny the use of the "k" in the labels disk and rdisk - I though disk was short for diskette???? an HDD is a Hard Disc Drive - but I guess we speak English as opposed to the strange dialect that we have to live with!)
Martin