Relative to MS Flight Sim (newest versions are only $29)
and multiple monitors.

I added a PCI video card to my PC so I could have
two side views (which was my biggest complaint about using sims).
I use the sim more as a procedure practice that actual flight practice, and
I hear it's a good way for IFR practice.

The cheapest way to get 3 (or 4) minotor views is to use 2 seperate cards
as opposed to a single 3 or 4 output card.

I use about 45 degree views left and right so they
more or less match with the front view.
It is a little tricky - you have to add windows when out of full-screen mode (see
the net/google regarding multiple monitor view help - there is support on the Microsoft page).
You drag the windows to each panel, then goto full screen more again, then
pan each individually to where you want it.

You are BEST to have the same manufacturer for both video cards - as I had some problems
when using different mfgs.
nVidia is a good choice. You could go with Matrox, too.
This means that you have a video card in the AGP slot, and one in a PCI slot.
I'd recommend 64Megs for each card - higher is better - although I currently have a 32Megs
in my AGP slot.

You could certianly actually add more if you wanted.
If you have 2 dual-monitor cards, you could use the 4th as a knee-board or other view,
which is handy.
(I've used this for learning checklist procedures prior to landing, or prior to takeoff, etc. . .)

Hope that this is some form of help,

Gary