2 disk setup - slightly OT

[blairg]

I have a very old PIII desktop running Win98 and an old hp compaq nx9005
laptop running Win XP Pro. When it became clear that I was not going to move
to Vista I thought I would look at Linux and in particular, ubuntu. I wanted
to leave my two old machines as they were so I decided to construct a new
desktop PC. At seventy years old and not having previously constructed a
computer or used Linux this was/is some challenge but the new machine is now
running ubuntu - ADM 64bit 7.04. I have two programs that only run in
Windows and I would like to run them on my new machine. I don't want to try
and run them under Wine.

What I have in mind is this:
1] put the current internal HD (Seagate Barracuda 7200.10 250Gb loaded with
ubuntu 7.04) into an external eSATA enclosure.
and
2] put three partitions - ext3, a FAT32 and a NTFS - on my current external
HD (a Seagate 250 Gb in a Vantec NexStar 3 NST-360SU enclosure) and install
Win XP Pro in the NTFS partition.

My hope is that my now "internal diskless" PC will boot up from whatever
external HD I plug into the eSATA plug on the computer case - ie, I will be
able to boot it to either a Windows PC or a ubuntu PC without having it set
up as a dual boot machine or having to change BIOS settings. Amongst other
things this will let me experiment with partition changes and do clean
re-installs of ubuntu (as I muck it up beyound my powers to recover a tidy
set-up !)on one disk without putting in danger my stable Windows setup.

I have two questions.

1] is this likely to work ?
and
2] what is my cheapest way of getting a legal copy of Win XP Pro ?. I have
the original Win 98 disk and Microsoft's 'Second Edition Udates' disks - I
think they can still be up-graded to Win XP Pro but I do not know how. I may
also be eligable for an Win XP Pro oem licence - but again, I do not know
how to claim it or which is the cheaper. Can anyone clear up my confusion ?


Thank you

blair