> ... Hauptwerk ... would be perfect, except (a) it costs money,
 > and (b) it's a bit too resource-hungry....

Hauptwerk - http://hauptwerk.co.uk - costs $ 90 US and is worth
every penny.  Martin Dyde has done a fantastic job.  He's working
on version 2.0 and has said that 1.x costs will apply towards an
upgrade to 2.0.  I'm a software developer and quite critical of
software in general.  Hauptwerk is nothing less than fantastic!

 > ... I have a P4/2.66 with 512mb ram running Win2K, a MIDI
 > interface, keyboard & pedalboard, a good sound card, and no
 > money.

Please check out my Hauptwerk Sample Comparison by Memory,
Stops, and Manuals

   http://midiorgan.com/virtualsamples/hauptwerkmemory.aspx

There are 10 or so organs that you can load w/512 MB.  I tried
out Hauptwerk with my P3m 1.2 Ghz notebook w/512MB RAM and
Windows XP Pro.  I didn't have a sound card as I used my
notebook's onboard sound.  It worked.  In fact you can try the
demo for free.  You'll just have to put up with a chime every
few bars.  Half of the sample sets at the low end of memory
requirements are free.  Three others range from $ 30 - $ 62 US.

Do not under estimate these small organs.  I have

http://www.milandigitalaudio.com/casavant17.htm
http://orgel.datzko.ch/Ott-Orgel-EN.html
http://www.sonusparadisi.cz/organs/zlkor/history.0.asp
http://www.postpiano.com/products/prod_iteminfo.php?id=28&subCat=Positif+Organ
http://www.organartmedia.com/Grieb-Intro.html

as well as Organ 1, Organ 2, and Organ 4.  And I have an organ
definition file for the 1654 Griebenow Positif Organ that
virtually adds a pedalboard.  As other posters have stated,
for home use less is more.  You don't need a huge sound every
time you practice.

By adding 512 MB or 1 GB of RAM you have many more options.
SF2 products do require fewer resources.  Give them a try and
go with whatever works for you.

Since you already have the prerequisites you're just looking
at a simulator, samples, and memory -- less than $ 500.  You
could try it out for free or take it for a spin for $ 90.

FYI
--
              |        Brian Wolfe, [log in to unmask]
    o    ___  ||       Founder & Principal, Habanero Software
   /\_  _|  | |||
  _\__`[___ | ||||     http://midiorgan.com
   ] [ \,/] | |||||    http://habanerosoftware.com
   -----==--+ !!!!!!.  http://home.austin.rr.com/losdos

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