Disklavier

I am finally thinking about entering the world of
digital audio recordings of piano performances.  I want
a portable set-up so I can record my Dad playing the
piano along with another person playing an old Hammond
organ.  I need to do better than a little boom box with
a cassette tape!   Since so many of you on this list do
such things, I would be interested in what you thought
of the following setup.

I am thinking about buying an Mbox packaged with
ProTools LE 6.7 and a Marshall Electronic MXL-2006
condenser mic, or rather a pair of mics.  I will use my
Evo laptop running XP sp1.

Would the MXL770 mic be better even though it is about
$20 cheaper?  What should be the criteria?

Should I go with ProTools LE 6.9 for an extra $100?
Are the newer file formats worth it, or the capability
to do step audio with video?

I am willing to throw about $600 into this project.  Am
I correct in thinking this would be better than using
my $20 Radio Shack mic plugged into the computer
soundcard using Cool Edit Lite?  Is there really a
difference in the quality of the finished product using
a more expensive audio to digital converter?

Thanks for any help!  If folks deem this question to
not be on topic with this list, please reply privately.
I know that I have a LOT of Disklavier clients who want
to make CD recordings of their piano playing, and I am
looking for a reasonably priced solution!

Carol Beigel
okay, so I know more about the piano, DKV and the MIDI,
but I am dead in the water on the digital recording
angle!