Thanks guys,
BOAC - I don't think I explained the reason for swapping clearly enough, apologies. All I want is to upgrade from Win2K to a clean install of XP, and changing over the HDD's would a) streamline my storage problems and b) hopefully make it a fairly straightforward process.
VAPilot - Sounds very promising thank you.
As it happens I have an unused computer that I'm rebuilding for a charity and I'll try it as an experiment before I mess with my data, will keep you posted.
Thanks
Just a thought I guess it would be better to do a clean XP install on the smaller HDD Pri Master (as I want) and then install the larger HDD as the Sec Master and let XP find the drives on reboot.